[Top][All Lists]
[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: bsearch utility
From: |
Sorav Bansal |
Subject: |
Re: bsearch utility |
Date: |
Tue, 26 Jul 2005 00:22:28 -0700 |
User-agent: |
Mozilla Thunderbird 1.0 (X11/20041206) |
Hmm, I see that compare.h contains some static functions. This is a
small point, but I'd rather treat those functions as potential
candidates for a library, which sort and look could share. So it'd be
better to have a compare.c that's compiled separately, to contain
those functions. Some of them would become extern.
Done. I agree, that static functions is not a good idea.
More important, there is still a lot of code duplication, e.g.,
the 'compare' function, and the body of 'main'. We can't remove
all the duplication, but still....
I have made an attempt to remove most duplication. Please let me know if more
can be done here.
The problem with using binary_search on non-regular files is that I
have no way of knowing the file size.
lseek with SEEK_END should tell you that, right?
Thats right. Done.
The old code looked like this:
if (! key->ignore)
key->ignore = nonprinting;
Oops. I was working on coreutils-5.0, and noticed that the later
versions have the bug fixed.
I have now ported look.c to the latest CVS repository too. In doing so,
I noticed that the new keycompare() function no longer calls
'trim_trailing_blanks()'. Its not clear to me, why these calls are not
necessary anymore. Is that because if the keys match till the last
non-blank character, then you allow the number of trailing blanks to be
considered as a tie-breaker?
These calls are needed for 'look' though. For now, I am adding the calls
and commenting with XXX in compare.h.
I don't see the need for the -B option, or the -l option. Can't
we omit them?
I thought '-l' could be useful for looking into unsorted files. '-B' can
be used for setting the buffer size which affects performance,
especially when doing linear search. However, I agree that they are not
particularly necessary.
Isn't fseeko kind of a loser, performance-wise? Wouldn't it
be faster if you used lseek, and took block boundaries into
account? I suppose this is more of a tuning thing tho.
How do you propose using block boundaries into account? I am not sure
what you mean, so I am leaving the fseeko() calls in place right now.
I would remove all that POSIX pedantic stuff from the option
parsing. It's not needed for 'look'. Just use getopt_long
as most other apps do.
Done.
The coding style in look.c is quite a bit different from that used
in coreutils. Please look to see how comments are done, indenting,
etc.
This time, I have tried my best to match the style in coreutils. Please
point me to specific areas where I am not conforming to the coding style
and I would be glad to correct them.
Regards,
Sorav
(4 files attached: compare.c, compare.h, look.c, sort.c)
#include <config.h>
#include <getopt.h>
#include <sys/types.h>
#include <signal.h>
#include "system.h"
#include "error.h"
#include "hard-locale.h"
#include "inttostr.h"
#include "physmem.h"
#include "posixver.h"
#include "quote.h"
#include "stdlib--.h"
#include "stdio--.h"
#include "strnumcmp.h"
#include "xmemcoll.h"
#include "xstrtol.h"
#include "compare.h"
/* Tab character separating fields. If TAB_DEFAULT, then fields are
separated by the empty string between a non-blank character and a blank
character. */
int tab = TAB_DEFAULT;
/* Nonzero if any of the input files are the standard input. */
bool have_read_stdin;
/* List of key field comparisons to be tried. */
struct keyfield *keylist;
/* The representation of the decimal point in the current locale. */
int decimal_point;
/* Thousands separator; if -1, then there isn't one. */
int thousands_sep;
/* Nonzero if the corresponding locales are hard. */
bool hard_LC_COLLATE;
#if HAVE_NL_LANGINFO
bool hard_LC_TIME;
#endif
/* FIXME: None of these tables work with multibyte character sets.
Also, there are many other bugs when handling multibyte characters.
One way to fix this is to rewrite `sort' to use wide characters
internally, but doing this with good performance is a bit
tricky. */
/* Table of blanks. */
bool blanks[UCHAR_LIM];
/* Table of non-printing characters. */
bool nonprinting[UCHAR_LIM];
/* Table of non-dictionary characters (not letters, digits, or blanks). */
bool nondictionary[UCHAR_LIM];
/* Translation table folding lower case to upper. */
char fold_toupper[UCHAR_LIM];
#define MONTHS_PER_YEAR 12
/* Table mapping month names to integers.
Alphabetic order allows binary search. */
struct month monthtab[] =
{
{"APR", 4},
{"AUG", 8},
{"DEC", 12},
{"FEB", 2},
{"JAN", 1},
{"JUL", 7},
{"JUN", 6},
{"MAR", 3},
{"MAY", 5},
{"NOV", 11},
{"OCT", 10},
{"SEP", 9}
};
/* The set of signals that are caught. */
sigset_t caught_signals;
/* Report MESSAGE for FILE, then clean up and exit.
If FILE is null, it represents standard output. */
void
die (char const *message, char const *file)
{
error (0, errno, "%s: %s", message, file ? file : _("standard output"));
exit (LOOK_SORT_FAILURE);
}
/* Return a stream for FILE, opened with mode HOW. A null FILE means
standard output; HOW should be "w". When opening for input, "-"
means standard input. To avoid confusion, do not return file
descriptors STDIN_FILENO, STDOUT_FILENO, or STDERR_FILENO when
opening an ordinary FILE. */
FILE *
xfopen (const char *file, const char *how)
{
FILE *fp;
if (!file)
fp = stdout;
else if (STREQ (file, "-") && *how == 'r')
{
have_read_stdin = true;
fp = stdin;
}
else
{
fp = fopen (file, how);
if (! fp)
die (_("open failed"), file);
}
return fp;
}
/* Close FP, whose name is FILE, and report any errors. */
void
xfclose (FILE *fp, char const *file)
{
switch (fileno (fp))
{
case STDIN_FILENO:
/* Allow reading stdin from tty more than once. */
if (feof (fp))
clearerr (fp);
break;
case STDOUT_FILENO:
/* Don't close stdout just yet. close_stdout does that. */
if (fflush (fp) != 0)
die (_("fflush failed"), file);
break;
default:
if (fclose (fp) != 0)
die (_("close failed"), file);
break;
}
}
#if HAVE_NL_LANGINFO
int
struct_month_cmp (const void *m1, const void *m2)
{
struct month const *month1 = m1;
struct month const *month2 = m2;
return strcmp (month1->name, month2->name);
}
#endif
/* Initialize the character class tables. */
void
inittables (void)
{
size_t i;
for (i = 0; i < UCHAR_LIM; ++i)
{
blanks[i] = !!ISBLANK (i);
nonprinting[i] = !ISPRINT (i);
nondictionary[i] = !ISALNUM (i) && !ISBLANK (i);
fold_toupper[i] = (ISLOWER (i) ? toupper (i) : i);
}
#if HAVE_NL_LANGINFO
/* If we're not in the "C" locale, read different names for months. */
if (hard_LC_TIME)
{
for (i = 0; i < MONTHS_PER_YEAR; i++)
{
char const *s;
size_t s_len;
size_t j;
char *name;
s = (char *) nl_langinfo (ABMON_1 + i);
s_len = strlen (s);
monthtab[i].name = name = xmalloc (s_len + 1);
monthtab[i].val = i + 1;
for (j = 0; j < s_len; j++)
name[j] = fold_toupper[to_uchar (s[j])];
name[j] = '\0';
}
qsort ((void *) monthtab, MONTHS_PER_YEAR,
sizeof *monthtab, struct_month_cmp);
}
#endif
}
/* Return a pointer to the first character of the field specified
by KEY in LINE. */
char *
begfield (const struct line *line, const struct keyfield *key)
{
char *ptr = line->text, *lim = ptr + line->length - 1;
size_t sword = key->sword;
size_t schar = key->schar;
size_t remaining_bytes;
/* The leading field separator itself is included in a field when -t
is absent. */
if (tab != TAB_DEFAULT)
while (ptr < lim && sword--)
{
while (ptr < lim && *ptr != tab)
++ptr;
if (ptr < lim)
++ptr;
}
else
while (ptr < lim && sword--)
{
while (ptr < lim && blanks[to_uchar (*ptr)])
++ptr;
while (ptr < lim && !blanks[to_uchar (*ptr)])
++ptr;
}
if (key->skipsblanks)
while (ptr < lim && blanks[to_uchar (*ptr)])
++ptr;
/* Advance PTR by SCHAR (if possible), but no further than LIM. */
remaining_bytes = lim - ptr;
if (schar < remaining_bytes)
ptr += schar;
else
ptr = lim;
return ptr;
}
/* Return the limit of (a pointer to the first character after) the field
in LINE specified by KEY. */
char *
limfield (const struct line *line, const struct keyfield *key)
{
char *ptr = line->text, *lim = ptr + line->length - 1;
size_t eword = key->eword, echar = key->echar;
size_t remaining_bytes;
/* Move PTR past EWORD fields or to one past the last byte on LINE,
whichever comes first. If there are more than EWORD fields, leave
PTR pointing at the beginning of the field having zero-based index,
EWORD. If a delimiter character was specified (via -t), then that
`beginning' is the first character following the delimiting TAB.
Otherwise, leave PTR pointing at the first `blank' character after
the preceding field. */
if (tab != TAB_DEFAULT)
while (ptr < lim && eword--)
{
while (ptr < lim && *ptr != tab)
++ptr;
if (ptr < lim && (eword | echar))
++ptr;
}
else
while (ptr < lim && eword--)
{
while (ptr < lim && blanks[to_uchar (*ptr)])
++ptr;
while (ptr < lim && !blanks[to_uchar (*ptr)])
++ptr;
}
#ifdef POSIX_UNSPECIFIED
/* The following block of code makes GNU sort incompatible with
standard Unix sort, so it's ifdef'd out for now.
The POSIX spec isn't clear on how to interpret this.
FIXME: request clarification.
From: address@hidden (Karl Heuer)
Date: Thu, 30 May 96 12:20:41 -0400
[Translated to POSIX 1003.1-2001 terminology by Paul Eggert.]
[...]I believe I've found another bug in `sort'.
$ cat /tmp/sort.in
a b c 2 d
pq rs 1 t
$ textutils-1.15/src/sort -k1.7,1.7 </tmp/sort.in
a b c 2 d
pq rs 1 t
$ /bin/sort -k1.7,1.7 </tmp/sort.in
pq rs 1 t
a b c 2 d
Unix sort produced the answer I expected: sort on the single character
in column 7. GNU sort produced different results, because it disagrees
on the interpretation of the key-end spec "M.N". Unix sort reads this
as "skip M-1 fields, then N-1 characters"; but GNU sort wants it to mean
"skip M-1 fields, then either N-1 characters or the rest of the current
field, whichever comes first". This extra clause applies only to
key-ends, not key-starts.
*/
/* Make LIM point to the end of (one byte past) the current field. */
if (tab != TAB_DEFAULT)
{
char *newlim;
newlim = memchr (ptr, tab, lim - ptr);
if (newlim)
lim = newlim;
}
else
{
char *newlim;
newlim = ptr;
while (newlim < lim && blanks[to_uchar (*newlim)])
++newlim;
while (newlim < lim && !blanks[to_uchar (*newlim)])
++newlim;
lim = newlim;
}
#endif
/* If we're ignoring leading blanks when computing the End
of the field, don't start counting bytes until after skipping
past any leading blanks. */
if (key->skipeblanks)
while (ptr < lim && blanks[to_uchar (*ptr)])
++ptr;
/* Advance PTR by ECHAR (if possible), but no further than LIM. */
remaining_bytes = lim - ptr;
if (echar < remaining_bytes)
ptr += echar;
else
ptr = lim;
return ptr;
}
/* Compare strings A and B as numbers without explicitly converting them to
machine numbers. Comparatively slow for short strings, but asymptotically
hideously fast. */
int
numcompare (const char *a, const char *b)
{
while (blanks[to_uchar (*a)])
a++;
while (blanks[to_uchar (*b)])
b++;
return strnumcmp (a, b, decimal_point, thousands_sep);
}
int
general_numcompare (const char *sa, const char *sb)
{
/* FIXME: add option to warn about failed conversions. */
/* FIXME: maybe add option to try expensive FP conversion
only if A and B can't be compared more cheaply/accurately. */
char *ea;
char *eb;
double a = strtod (sa, &ea);
double b = strtod (sb, &eb);
/* Put conversion errors at the start of the collating sequence. */
if (sa == ea)
return sb == eb ? 0 : -1;
if (sb == eb)
return 1;
/* Sort numbers in the usual way, where -0 == +0. Put NaNs after
conversion errors but before numbers; sort them by internal
bit-pattern, for lack of a more portable alternative. */
return (a < b ? -1
: a > b ? 1
: a == b ? 0
: b == b ? -1
: a == a ? 1
: memcmp ((char *) &a, (char *) &b, sizeof a));
}
/* Return an integer in 1..12 of the month name MONTH with length LEN.
Return 0 if the name in S is not recognized. */
int
getmonth (char const *month, size_t len)
{
size_t lo = 0;
size_t hi = MONTHS_PER_YEAR;
char const *monthlim = month + len;
for (;;)
{
if (month == monthlim)
return 0;
if (!blanks[to_uchar (*month)])
break;
++month;
}
do
{
size_t ix = (lo + hi) / 2;
char const *m = month;
char const *n = monthtab[ix].name;
for (;; m++, n++)
{
if (!*n)
return monthtab[ix].val;
if (m == monthlim || fold_toupper[to_uchar (*m)] < to_uchar (*n))
{
hi = ix;
break;
}
else if (fold_toupper[to_uchar (*m)] > to_uchar (*n))
{
lo = ix + 1;
break;
}
}
}
while (lo < hi);
return 0;
}
void
trim_trailing_blanks (const char *a_start, char **a_end)
{
while (*a_end > a_start && blanks[to_uchar (*(*a_end - 1))])
--(*a_end);
}
/* Compare two lines A and B trying every key in sequence until there
are no more keys or a difference is found. */
int
keycompare (const struct line *a, const struct line *b)
{
struct keyfield const *key = keylist;
/* For the first iteration only, the key positions have been
precomputed for us. */
char *texta = a->keybeg;
char *textb = b->keybeg;
char *lima = a->keylim;
char *limb = b->keylim;
char *i ;
int diff;
for (;;)
{
char const *translate = key->translate;
bool const *ignore = key->ignore;
/* Find the lengths. */
size_t lena = lima <= texta ? 0 : lima - texta;
size_t lenb = limb <= textb ? 0 : limb - textb;
/* XXX: added this */
if (key->skipeblanks)
{
char *a_end = texta + lena;
char *b_end = textb + lenb;
trim_trailing_blanks (texta, &a_end);
trim_trailing_blanks (textb, &b_end);
lena = a_end - texta;
lenb = b_end - textb;
}
/* XXX: added this */
/* Actually compare the fields. */
if (key->numeric | key->general_numeric)
{
char savea = *lima, saveb = *limb;
*lima = *limb = '\0';
diff = ((key->numeric ? numcompare : general_numcompare)
(texta, textb));
*lima = savea, *limb = saveb;
}
else if (key->month)
diff = getmonth (texta, lena) - getmonth (textb, lenb);
/* Sorting like this may become slow, so in a simple locale the user
can select a faster sort that is similar to ascii sort. */
else if (hard_LC_COLLATE)
{
if (ignore || translate)
{
char buf[4000];
size_t size = lena + 1 + lenb + 1;
char *copy_a = (size <= sizeof buf ? buf : xmalloc (size));
char *copy_b = copy_a + lena + 1;
size_t new_len_a, new_len_b, i;
/* Ignore and/or translate chars before comparing. */
for (new_len_a = new_len_b = i = 0; i < MAX (lena, lenb); i++)
{
if (i < lena)
{
copy_a[new_len_a] = (translate
? translate[to_uchar (texta[i])]
: texta[i]);
if (!ignore || !ignore[to_uchar (texta[i])])
++new_len_a;
}
if (i < lenb)
{
copy_b[new_len_b] = (translate
? translate[to_uchar (textb[i])]
: textb [i]);
if (!ignore || !ignore[to_uchar (textb[i])])
++new_len_b;
}
}
diff = xmemcoll (copy_a, new_len_a, copy_b, new_len_b);
if (sizeof buf < size)
free (copy_a);
}
else if (lena == 0)
diff = - NONZERO (lenb);
else if (lenb == 0)
goto greater;
else
diff = xmemcoll (texta, lena, textb, lenb);
}
else if (ignore)
{
#define CMP_WITH_IGNORE(A, B) \
do \
{ \
for (;;) \
{ \
while (texta < lima && ignore[to_uchar (*texta)]) \
++texta; \
while (textb < limb && ignore[to_uchar (*textb)]) \
++textb; \
if (! (texta < lima && textb < limb)) \
break; \
diff = to_uchar (A) - to_uchar (B); \
if (diff) \
goto not_equal; \
++texta; \
++textb; \
} \
\
diff = (texta < lima) - (textb < limb); \
} \
while (0)
if (translate)
CMP_WITH_IGNORE (translate[to_uchar (*texta)],
translate[to_uchar (*textb)]);
else
CMP_WITH_IGNORE (*texta, *textb);
}
else if (lena == 0)
diff = - NONZERO (lenb);
else if (lenb == 0)
goto greater;
else
{
if (translate)
{
while (texta < lima && textb < limb)
{
diff = (to_uchar (translate[to_uchar (*texta++)])
- to_uchar (translate[to_uchar (*textb++)]));
if (diff)
goto not_equal;
}
}
else
{
diff = memcmp (texta, textb, MIN (lena, lenb));
if (diff)
goto not_equal;
}
diff = lena < lenb ? -1 : lena != lenb;
}
if (diff)
goto not_equal;
key = key->next;
if (! key)
break;
/* Find the beginning and limit of the next field. */
if (key->eword != SIZE_MAX)
lima = limfield (a, key), limb = limfield (b, key);
else
lima = a->text + a->length - 1, limb = b->text + b->length - 1;
if (key->sword != SIZE_MAX)
texta = begfield (a, key), textb = begfield (b, key);
else
{
texta = a->text, textb = b->text;
if (key->skipsblanks)
{
while (texta < lima && blanks[to_uchar (*texta)])
++texta;
while (textb < limb && blanks[to_uchar (*textb)])
++textb;
}
}
}
return 0;
greater:
diff = 1;
not_equal:
return key->reverse ? -diff : diff;
}
/* Insert key KEY at the end of the key list. */
void
insertkey (struct keyfield *key)
{
struct keyfield **p;
for (p = &keylist; *p; p = &(*p)->next)
continue;
*p = key;
key->next = NULL;
}
/* Report a bad field specification SPEC, with extra info MSGID. */
void
badfieldspec (char const *spec, char const *msgid)
{
error (LOOK_SORT_FAILURE, 0, _("%s: invalid field specification %s"),
_(msgid), quote (spec));
abort ();
}
/* Parse the leading integer in STRING and store the resulting value
(which must fit into size_t) into *VAL. Return the address of the
suffix after the integer. If MSGID is NULL, return NULL after
failure; otherwise, report MSGID and exit on failure. */
char const *
parse_field_count (char const *string, size_t *val, char const *msgid)
{
char *suffix;
uintmax_t n;
switch (xstrtoumax (string, &suffix, 10, &n, ""))
{
case LONGINT_OK:
case LONGINT_INVALID_SUFFIX_CHAR:
*val = n;
if (*val == n)
break;
/* Fall through. */
case LONGINT_OVERFLOW:
case LONGINT_OVERFLOW | LONGINT_INVALID_SUFFIX_CHAR:
if (msgid)
error (LOOK_SORT_FAILURE, 0, _("%s: count `%.*s' too large"),
_(msgid), (int) (suffix - string), string);
return NULL;
case LONGINT_INVALID:
if (msgid)
error (LOOK_SORT_FAILURE, 0, _("%s: invalid count at start of %s"),
_(msgid), quote (string));
return NULL;
}
return suffix;
}
/* Set the ordering options for KEY specified in S.
Return the address of the first character in S that
is not a valid ordering option.
BLANKTYPE is the kind of blanks that 'b' should skip. */
char *
set_ordering (const char *s, struct keyfield *key, enum blanktype blanktype)
{
while (*s)
{
switch (*s)
{
case 'b':
if (blanktype == bl_start || blanktype == bl_both)
key->skipsblanks = true;
if (blanktype == bl_end || blanktype == bl_both)
key->skipeblanks = true;
break;
case 'd':
key->ignore = nondictionary;
break;
case 'f':
key->translate = fold_toupper;
break;
case 'g':
key->general_numeric = true;
break;
case 'i':
/* Option order should not matter, so don't let -i override
-d. -d implies -i, but -i does not imply -d. */
if (! key->ignore)
key->ignore = nonprinting;
break;
case 'M':
key->month = true;
break;
case 'n':
key->numeric = true;
break;
case 'r':
key->reverse = true;
break;
default:
return (char *) s;
}
++s;
}
return (char *) s;
}
struct keyfield *
new_key (void)
{
struct keyfield *key = xzalloc (sizeof *key);
key->eword = SIZE_MAX;
return key;
}
/* Get locale's representation of the decimal point */
void
init_locale_decimal_point (void)
{
struct lconv const *locale = localeconv ();
/* If the locale doesn't define a decimal point, or if the decimal
point is multibyte, use the C locale's decimal point. FIXME:
add support for multibyte decimal points. */
decimal_point = to_uchar (locale->decimal_point[0]);
if (! decimal_point || locale->decimal_point[1])
decimal_point = '.';
/* FIXME: add support for multibyte thousands separators. */
thousands_sep = to_uchar (*locale->thousands_sep);
if (! thousands_sep || locale->thousands_sep[1])
thousands_sep = -1;
}
void
build_key (char const *keyarg)
{
struct keyfield *key;
char const *s ;
key = new_key ();
/* Get POS1. */
s = parse_field_count (keyarg, &key->sword,
N_("invalid number at field start"));
if (! key->sword--)
{
/* Provoke with `sort -k0' */
badfieldspec (keyarg, N_("field number is zero"));
}
if (*s == '.')
{
s = parse_field_count (s + 1, &key->schar,
N_("invalid number after `.'"));
if (! key->schar--)
{
/* Provoke with `sort -k1.0' */
badfieldspec (keyarg, N_("character offset is zero"));
}
}
if (! (key->sword | key->schar))
key->sword = SIZE_MAX;
s = set_ordering (s, key, bl_start);
if (*s != ',')
{
key->eword = SIZE_MAX;
key->echar = 0;
}
else
{
/* Get POS2. */
s = parse_field_count (s + 1, &key->eword,
N_("invalid number after `,'"));
if (! key->eword--)
{
/* Provoke with `sort -k1,0' */
badfieldspec (keyarg, N_("field number is zero"));
}
if (*s == '.')
s = parse_field_count (s + 1, &key->echar,
N_("invalid number after `.'"));
else
{
/* `-k 2,3' is equivalent to `+1 -3'. */
key->eword++;
}
s = set_ordering (s, key, bl_end);
}
if (*s)
badfieldspec (keyarg, N_("stray character in field spec"));
insertkey (key);
}
#ifndef COMPARE_H
# define COMPARE_H
#if HAVE_LANGINFO_CODESET
# include <langinfo.h>
#endif
#define UCHAR_LIM (UCHAR_MAX + 1)
/* Exit statuses. */
enum
{
/* exit with status 1 if no matching line was found by look */
LOOK_NOT_FOUND = 1,
/* POSIX says sort to exit with status 1 if invoked with -c and the
input is not properly sorted. */
SORT_OUT_OF_ORDER = 1,
/* POSIX says any other irregular exit must exit with a status
code greater than 1. */
LOOK_SORT_FAILURE = 2
};
#define NONZERO(x) ((x) != 0)
/* The kind of blanks for '-b' to skip in various options. */
enum blanktype { bl_start, bl_end, bl_both };
/* The character marking end of line. Default to \n. */
static char eolchar = '\n';
/* Lines are held in core as counted strings. */
struct line
{
char *text; /* Text of the line. */
size_t length; /* Length including final newline. */
char *keybeg; /* Start of first key. */
char *keylim; /* Limit of first key. */
};
/* Input buffers. */
struct buffer
{
char *buf; /* Dynamically allocated buffer,
partitioned into 3 regions:
- input data;
- unused area;
- an array of lines, in reverse order. */
size_t used; /* Number of bytes used for input data. */
size_t nlines; /* Number of lines in the line array. */
size_t alloc; /* Number of bytes allocated. */
size_t left; /* Number of bytes left from previous reads. */
size_t line_bytes; /* Number of bytes to reserve for each line. */
bool eof; /* An EOF has been read. */
};
struct keyfield
{
size_t sword; /* Zero-origin 'word' to start at. */
size_t schar; /* Additional characters to skip. */
size_t eword; /* Zero-origin first word after field. */
size_t echar; /* Additional characters in field. */
bool const *ignore; /* Boolean array of characters to ignore. */
char const *translate; /* Translation applied to characters. */
bool skipsblanks; /* Skip leading blanks when finding start. */
bool skipeblanks; /* Skip leading blanks when finding end. */
bool numeric; /* Flag for numeric comparison. Handle
strings of digits with optional decimal
point, but no exponential notation. */
bool general_numeric; /* Flag for general, numeric comparison.
Handle numbers in exponential notation. */
bool month; /* Flag for comparison by month name. */
bool reverse; /* Reverse the sense of comparison. */
struct keyfield *next; /* Next keyfield to try. */
};
struct month
{
char const *name;
int val;
};
/* If TAB has this value, blanks separate fields. */
enum { TAB_DEFAULT = CHAR_MAX + 1 };
/* Tab character separating fields. If TAB_DEFAULT, then fields are
separated by the empty string between a non-blank character and a blank
character. */
extern int tab ;
/* Nonzero if any of the input files are the standard input. */
extern bool have_read_stdin;
/* List of key field comparisons to be tried. */
extern struct keyfield *keylist;
/* The representation of the decimal point in the current locale. */
extern int decimal_point;
/* Thousands separator; if -1, then there isn't one. */
extern int thousands_sep;
/* Nonzero if the corresponding locales are hard. */
extern bool hard_LC_COLLATE;
#if HAVE_NL_LANGINFO
extern bool hard_LC_TIME;
#endif
/* FIXME: None of these tables work with multibyte character sets.
Also, there are many other bugs when handling multibyte characters.
One way to fix this is to rewrite `sort' to use wide characters
internally, but doing this with good performance is a bit
tricky. */
/* Table of blanks. */
extern bool blanks[UCHAR_LIM];
/* Table of non-printing characters. */
extern bool nonprinting[UCHAR_LIM];
/* Table of non-dictionary characters (not letters, digits, or blanks). */
extern bool nondictionary[UCHAR_LIM];
/* Translation table folding lower case to upper. */
extern char fold_toupper[UCHAR_LIM];
/* The set of signals that are caught. */
extern sigset_t caught_signals;
/* Report MESSAGE for FILE, then clean up and exit.
If FILE is null, it represents standard output. */
extern void die (char const *, char const *) ATTRIBUTE_NORETURN;
/* Return a stream for FILE, opened with mode HOW. A null FILE means
standard output; HOW should be "w". When opening for input, "-"
means standard input. To avoid confusion, do not return file
descriptors STDIN_FILENO, STDOUT_FILENO, or STDERR_FILENO when
opening an ordinary FILE. */
extern FILE *xfopen (const char *file, const char *how) ;
/* Close FP, whose name is FILE, and report any errors. */
extern void xfclose (FILE *fp, char const *file) ;
#if HAVE_NL_LANGINFO
extern int struct_month_cmp (const void *m1, const void *m2) ;
#endif
/* Initialize the character class tables. */
extern void inittables (void) ;
/* Return a pointer to the first character of the field specified
by KEY in LINE. */
extern char *begfield (const struct line *line, const struct keyfield *key);
/* Return the limit of (a pointer to the first character after) the field
in LINE specified by KEY. */
extern char *limfield (const struct line *line, const struct keyfield *key);
/* Compare strings A and B as numbers without explicitly converting them to
machine numbers. Comparatively slow for short strings, but asymptotically
hideously fast. */
extern int numcompare (const char *a, const char *b);
extern int general_numcompare (const char *sa, const char *sb);
/* Return an integer in 1..12 of the month name MONTH with length LEN.
Return 0 if the name in S is not recognized. */
extern int getmonth (char const *month, size_t len);
/* Compare two lines A and B trying every key in sequence until there
are no more keys or a difference is found. */
extern int keycompare (const struct line *a, const struct line *b);
/* Insert key KEY at the end of the key list. */
extern void insertkey (struct keyfield *key);
/* Report a bad field specification SPEC, with extra info MSGID. */
extern void badfieldspec (char const *, char const *) ATTRIBUTE_NORETURN;
/* Parse the leading integer in STRING and store the resulting value
(which must fit into size_t) into *VAL. Return the address of the
suffix after the integer. If MSGID is NULL, return NULL after
failure; otherwise, report MSGID and exit on failure. */
extern char const *parse_field_count (char const *string, size_t *val,
char const *msgid);
/* Set the ordering options for KEY specified in S.
Return the address of the first character in S that
is not a valid ordering option.
BLANKTYPE is the kind of blanks that 'b' should skip. */
extern char *set_ordering (const char *s, struct keyfield *key,
enum blanktype blanktype);
/* Allocate, initialize and return a new key */
extern struct keyfield *new_key (void);
/* Get locale's representation of the decimal point */
extern void init_locale_decimal_point (void);
/* Build a key using string keyarg passed with -k */
extern void build_key (char const *keyarg);
/* Trim trailing blanks for string between a_start and *a_end. Decrement
*a_end appropriately. */
extern void trim_trailing_blanks (const char *a_start, char **a_end);
#endif
/* look: Submitted for code review by Sorav Bansal (address@hidden)
to address@hidden
*/
#include <config.h>
#include <getopt.h>
#include <sys/types.h>
#include <signal.h>
#include <stdio.h>
#include <assert.h>
#include "system.h"
#include "long-options.h"
#include "error.h"
#include "hard-locale.h"
#include "inttostr.h"
#include "physmem.h"
#include "posixver.h"
#include "stdio-safer.h"
#include "xmemcoll.h"
#include "xstrtol.h"
#include "compare.h"
#include "exitfail.h"
#define PATH_WORDS "/usr/share/dict/words"
/* The official name of this program (e.g., no `g' prefix). */
#define PROGRAM_NAME "look"
#define AUTHORS N_ ("\'Under Review\'")
#if HAVE_LANGINFO_CODESET
# include <langinfo.h>
#endif
/* Minimum disk transfer size */
#define DISK_SECTOR_SIZE (512)
struct line_buffer
{
char *buf ;
size_t alloc;
struct line line ;
};
/* The approximate length of a line (setting this speeds up the iterative
procedure to infer line length) */
static size_t default_line_size = DISK_SECTOR_SIZE ;
/* Flag to reverse the order of all comparisons. */
static int reverse;
/* Flag to ignore nondictionary characters. Used when no key is specified */
static int dflag = 0 ;
/* Flag to ignore nonprinting characters. Used when no key is specified */
static int iflag = 0 ;
/* Flag to fold all characters to uppercase. Used when no key is specified */
static int fflag = 0 ;
/* Flag to indicate that we should use only linear search */
static int lflag = 0 ;
/* Exit status: Default is 1 (indicating that no line was found) */
static int exit_status = LOOK_NOT_FOUND ;
/* The name this program was run with. */
char *program_name;
/* Pointer to the string holding the output file */
char const *output_file = NULL ;
void
usage (int status)
{
if (status != 0)
fprintf (stderr, _("Try `%s --help' for more information.\n"),
program_name);
else
{
printf (_("\
Usage: %s [OPTION]... STRING [FILE]...\n\
"),
program_name);
fputs (_("\
Display lines matching a STRING and given key fields using binary search in a\n\
sorted file FILE. If FILE is not specified, the file '/usr/share/dict/words'\n\
is used, only alphanumeric characters are compared and the case of alphabetic\n\
characters is ignored. \n\n\
As look performs a binary search, the lines in FILE must be sorted (where\n\
sort(1) got the same options as look is invoked with). If keyfields are not\n\
specified using '-k', look displays any lines in FILE which contains STRING\n\
as a prefix (still honoring the -d and -f options).\n\n\
Ordering options:\n\
\n\
"), stdout);
fputs (_("\
Mandatory arguments to long options are mandatory for short options too.\n\
"), stdout);
fputs (_("\
-B, --buffer-size=SIZE use SIZE as the average line buffer size\n\
-d, --dictionary-order consider only blanks and alphanumeric characters\n\
-f, --ignore-case fold lower case to upper case characters\n\
"), stdout);
fputs (_("\
-i, --ignore-nonprinting consider only printable characters\n\
-l, --linear-search Use linear search only (don't use binary search)\n\
-o, --output=FILE write result to FILE instead of standard output\n\
-r, --reverse the file was sorted using reverse order\n\
\n\
"), stdout);
fputs (_("\
Other options:\n\
\n\
-b, --ignore-leading-blanks ignore leading blanks (useful only with -k)\n\
-g, --general-numeric-comp compare according to general numerical value
(useful only with -k)\n\
-k, --key=POS1[,POS2] start a key at POS1, end it at POS 2 (origin 1)\n\
-M, --month-compare compare (unknown) < `JAN' < ... < `DEC' (useful
only with -k)\n\
-n, --numeric-compare compare according to string numerical value
(useful only with -k)\n\
"), stdout);
printf (_("\
-t, --field-separator=SEP use SEP instead of non- to whitespace transition\n\
"));
fputs (_("\
-z, --zero-terminated lines end with 0 byte, not newline\n\
"), stdout);
fputs (HELP_OPTION_DESCRIPTION, stdout);
fputs (VERSION_OPTION_DESCRIPTION, stdout);
fputs (_("\
\n\
POS is F[.C][OPTS], where F is the field number and C the character position\n\
in the field. OPTS is one or more single-letter ordering options, which\n\
override global ordering options for that key. If no key is given, use the\n\
entire line as the key.\n\
\n\
SIZE may be followed by the following multiplicative suffixes:\n\
"), stdout);
fputs (_("\
b 1, K 1024 (default), and so on for M, G, T, P, E, Z, Y.\n\
\n\
With no FILE, or when FILE is -, read standard input.\n\
\n\
*** WARNING ***\n\
The locale specified by the environment affects search and sort order.\n\
Set LC_ALL=C to get the traditional sort order that uses\n\
native byte values.\n\
"), stdout );
printf (_("\nReport bugs to <%s>.\n"), PACKAGE_BUGREPORT);
}
assert (status == 0 || status == LOOK_SORT_FAILURE);
exit (status);
}
static char const short_options[] = "bdfgik:lMno:rB:t:z";
static struct option const long_options[] =
{
{"ignore-leading-blanks", no_argument, NULL, 'b'},
{"dictionary-order", no_argument, NULL, 'd'},
{"ignore-case", no_argument, NULL, 'f'},
{"general-numeric-comp", no_argument, NULL, 'g'},
{"ignore-nonprinting", no_argument, NULL, 'i'},
{"key", required_argument, NULL, 'k'},
{"linear-search", no_argument, NULL, 'l'},
{"month-compare", no_argument, NULL, 'M'},
{"numeric-compare", no_argument, NULL, 'n'},
{"output", required_argument, NULL, 'o'},
{"reverse", no_argument, NULL, 'r'},
{"buffer-size", required_argument, NULL, 'B'},
{"field-separator", required_argument, NULL, 't'},
{"zero-terminated", no_argument, NULL, 'z'},
{GETOPT_HELP_OPTION_DECL},
{GETOPT_VERSION_OPTION_DECL},
{0, 0, 0, 0},
};
/* Specify the average size of a line (this can speed up the iterative
process of inferring the length of a line) */
static void
specify_line_size (char const *s)
{
uintmax_t n;
char *suffix;
enum strtol_error e = xstrtoumax (s, &suffix, 10, &n, "EgGkKmMPtTYZ");
/* The default unit is KiB. */
if (e == LONGINT_OK && ISDIGIT (suffix[-1]))
{
if (n <= UINTMAX_MAX / 1024)
n *= 1024;
else
e = LONGINT_OVERFLOW;
}
/* A 'b' suffix means bytes; a '%' suffix means percent of memory. */
if (e == LONGINT_INVALID_SUFFIX_CHAR && ISDIGIT (suffix[-1]) && ! suffix[1])
switch (suffix[0])
{
case 'b':
e = LONGINT_OK;
break;
case '%':
{
double mem = physmem_total () * n / 100;
/* Use "<", not "<=", to avoid problems with rounding. */
if (mem < UINTMAX_MAX)
{
n = mem;
e = LONGINT_OK;
}
else
e = LONGINT_OVERFLOW;
}
break;
}
if (e == LONGINT_OK)
{
default_line_size = n;
if (default_line_size == n)
{
default_line_size = MAX (default_line_size, DISK_SECTOR_SIZE);
return;
}
e = LONGINT_OVERFLOW;
}
STRTOL_FATAL_ERROR (s, _("line size"), e);
}
static void
init_line_buffer (struct line_buffer *buf, size_t alloc)
{
for (;;)
{
buf->buf = malloc (alloc);
if (buf->buf)
break;
alloc /= 2;
if (alloc <= 1)
xalloc_die ();
}
buf->alloc = alloc;
buf->line.text = NULL ;
buf->line.length = 0 ;
}
/* Fill LINE with the addresses START and END that denote the start and end
of the line respectively. Also, precompute the position of the first key
*/
static void
make_line (struct line *line, char *start, char *end)
{
struct keyfield const *key = keylist ;
line->text = start ;
line->length = (end - start) + 1 ;
if (key) {
/* Precompute the position of the first key for
efficiency. */
line->keylim = (key->eword == SIZE_MAX
? end
: limfield (line, key));
if (key->sword != SIZE_MAX)
line->keybeg = begfield (line, key);
else
{
if (key->skipsblanks)
while (blanks[to_uchar (*start)])
start++;
line->keybeg = start;
}
/* trim trailing blanks */
if (key->skipeblanks)
trim_trailing_blanks (line->keybeg, &line->keylim);
}
}
/* Get the closest line starting at BEGIN in file FILE (pointed to by FP).
* The closest line is obtained by searching for the next two EOL characters
* and filling BUF with the line represented by the characters in between.
* BUF is realloc()ed if needed to fit the line. The function returns the
* file offset of the returned line, if successful. Returns -1 if no line
* was found starting at BEGIN, or an error was encountered
*/
static off_t
get_closest_line (struct line_buffer *buf,
off_t begin,
register FILE *fp,
char const *file)
{
size_t start = 0 ; /* start should be >0 to be meaningful */
size_t buf_used = 0 ;
if (fseeko (fp, begin, SEEK_SET) < 0)
die (_("seek error"), file);
for (;;)
{
char *ptr = buf->buf + buf_used ;
size_t readsize = (buf->alloc - 1) - buf_used ;
size_t bytes_read = fread (ptr, 1, readsize, fp) ;
char *ptrlim = ptr + bytes_read ;
char *p ;
if (bytes_read != readsize)
{
if (ferror (fp))
die (_("read failed"), file) ;
if (feof (fp))
{
if (buf->buf == ptrlim)
return -1 ;
if (ptrlim[-1] != eolchar)
*ptrlim++ = eolchar ;
}
}
if (!start)
{
if ((p = memchr (ptr, eolchar, ptrlim - ptr)))
start = (p - buf->buf) + 1 ;
}
if (start)
{
char *ptr_start = buf->buf + start ;
char *scan_start = MAX (ptr_start, ptr) ;
char *end ;
if ((end = memchr (scan_start, eolchar, ptrlim - scan_start)))
{
make_line (&buf->line, ptr_start, end) ;
return (ftello(fp) + (ptr_start-ptrlim)) ;
}
}
if (feof (fp))
return -1 ;
buf_used = ptrlim - buf->buf ;
/* The current input line is too long to fit in the buffer.
Double the buffer size and try again. */
if (2 * buf->alloc < buf->alloc)
xalloc_die ();
buf->alloc *= 2;
buf->buf = xrealloc (buf->buf, buf->alloc);
}
}
/* Compare two lines A and B, returning negative, zero, or positive
depending on whether A compares less than, equal to, or greater than B.
If no keylist is specified, check to see if B is a substring of A. If B
is a substring of A, return 0. Else, return negative or positive depending
on the first character that differs */
static int
compare (register const struct line *a, register const struct line *b)
{
int diff = 0 ;
size_t alen, blen, minlen ;
size_t i,j ;
char ch ;
/* First try to compare on the specified keys (if any). */
if (keylist)
{
diff = keycompare (a, b) ;
return (diff);
}
/* Use the default prefix-matching. Check to see if b is a prefix
of a. This logic understands the -f, -d and -i flags */
alen = a->length - 1, blen = b->length - 1;
char *copy_a = a->text ;
char *copy_b = b->text ;
size_t new_alen = alen, new_blen = blen ;
if (fflag || dflag || iflag)
{
copy_a = (char *) alloca (alen + 1);
/* Ignore and/or translate chars for 'a' before comparing.
The translation for 'b' must have already been done once
in the beginning
*/
for (new_alen = i = 0; i < alen; i++)
{
unsigned char ch = to_uchar (a->text[i]) ;
if ((!dflag || !nondictionary[ch])
&& (!iflag || !nonprinting[ch]))
{
copy_a [new_alen++] = fflag ? fold_toupper [ch] : ch ;
}
}
}
if (new_alen == 0)
diff = - NONZERO (new_blen);
else if (new_blen == 0)
diff = NONZERO (new_alen);
else
{
size_t minlen = MIN (new_alen, new_blen) ;
if (HAVE_SETLOCALE && hard_LC_COLLATE)
{
if (!(diff = xmemcoll (copy_a, minlen, copy_b, minlen)))
{
if (new_alen < new_blen)
diff = -1 ;
}
}
else if (! (diff = memcmp (copy_a, copy_b, minlen )))
{
if (new_alen < new_blen)
diff = -1 ;
}
}
return reverse ? -diff : diff;
}
static void
write_line (FILE *fp, struct line *line, char const *file)
{
if (fwrite (line->text, line->length, 1, fp) < 1)
die (_("write failed"), file);
exit_status = 0 ;
}
/* Search STRING in FILE using linear search starting at offset FRONT. Use
BUF as a temporary in-memory buffer, increasing its size if needed. */
static void
linear_search (struct line const *line, FILE *fp, char const *file,
off_t front, struct line_buffer *buf)
{
FILE *ofp ;
int comp ;
size_t buf_used = 0 ;
ofp = xfopen (output_file, "w") ;
if ((front >= 0) && (fseeko (fp, front, SEEK_SET) < 0))
die (_("seek failed"), file);
for (;;)
{
char *ptr = buf->buf + buf_used ;
size_t readsize = (buf->buf + (buf->alloc - 1)) - ptr ;
size_t bytes_read = fread (ptr, 1, readsize, fp) ;
char *ptrlim = ptr + bytes_read ;
char *p ;
if (bytes_read != readsize)
{
if (ferror (fp))
die (_("read failed"), file) ;
if (feof (fp))
{
if (buf->buf == ptrlim)
{
goto done ;
}
if (ptrlim[-1] != eolchar)
*ptrlim++ = eolchar ;
}
}
if ((p = memchr (ptr, eolchar, ptrlim - ptr)))
{
make_line (&buf->line, buf->buf, p) ;
ptr = p+1 ;
if (!lflag && 0 < (comp = compare (&buf->line, line)))
{
goto done ;
}
else
if (0 == comp)
{
write_line (ofp, &buf->line, output_file) ;
}
/* ptr now points to the start of next line */
while ((p = memchr (ptr, eolchar, ptrlim - ptr)))
{
make_line (&buf->line, ptr, p) ;
ptr = p+1 ;
if (!lflag && 0 < (comp = compare (&buf->line, line)))
{
goto done ;
}
else
if (0 == comp)
{
write_line (ofp, &buf->line, output_file) ;
}
}
buf_used = ptrlim - ptr ;
memmove (buf->buf, ptr, buf_used) ;
}
else
{
buf_used = ptrlim - buf->buf ;
/* The current input line is too long to fit in the buffer.
Double the buffer size and try again. */
if (2 * buf->alloc < buf->alloc)
xalloc_die ();
buf->alloc *= 2;
buf->buf = xrealloc (buf->buf, buf->alloc);
}
}
done:
xfclose (ofp, output_file) ;
return ;
}
/* Search a line matching LINE in FILE using binary search
Invariants:
front points to the the beginning of a line at or before the first
matching line.
back points to the beginning of a line at or after the first matching
line.
Base of the Invariants:
front = NULL ;
back = EOF ;
Advancing the Invariants:
median = first newline after halfway point from front to back
If the string at "median" is not greater than the string to match,
median is the new front. Otherwise it is the new back.
Termination:
The binary search procedure exits if front==back and hence a matching
line could not be found.
It lends way to linear_search if "median" equals "back". This implies
that there exists a string at least half as long as (back-front),
which implies that a linear search will be no more expensive than
the cost of simply printing a string or two.
Trying to continue with binary search at this point will be more
trouble than it's worth.
This algorithm was inspired by the look utility available as part
of GNU bsdadminutils package. */
static void
binary_search (struct line const *line, char const *file)
{
struct line_buffer buf ;
static size_t disk_read_size = 0 ;
FILE *fp = xfopen (file, "r");
struct stat st ;
off_t front, back, median ;
disk_read_size = MAX (DISK_SECTOR_SIZE, default_line_size) ;
init_line_buffer (&buf, disk_read_size) ;
front = 0;
if (lflag || (fseeko (fp, 0, SEEK_END)) < 0)
{
linear_search (line, fp, file, -1, &buf);
goto done;
}
back = ftello (fp);
for (;;)
{
if (front==back)
goto done ;
median = front + (back-front)/2 ;
if (((median = get_closest_line (&buf, median, fp, file)) < 0)
|| (median == back) || (back - front < buf.alloc))
{
linear_search (line, fp, file, front, &buf) ;
goto done ;
}
if (0 > compare (&buf.line, line))
front = median ;
else
back = median ;
}
done:
xfclose (fp, file) ;
free (buf.buf) ;
return ;
}
int
main (int argc, char **argv)
{
struct keyfield *key;
struct keyfield gkey;
char const *s;
int c = 0;
size_t nfiles = 0;
char *minus = "-", *dictionary = PATH_WORDS, *file;
char const *outfile = NULL;
char *string ;
initialize_main (&argc, &argv);
program_name = argv[0];
setlocale (LC_ALL, "");
bindtextdomain (PACKAGE, LOCALEDIR);
textdomain (PACKAGE);
initialize_exit_failure (LOOK_SORT_FAILURE);
atexit (close_stdout);
hard_LC_COLLATE = hard_locale (LC_COLLATE);
#if HAVE_NL_LANGINFO
hard_LC_TIME = hard_locale (LC_TIME);
#endif
init_locale_decimal_point ();
have_read_stdin = false;
inittables ();
gkey.sword = gkey.eword = SIZE_MAX ;
gkey.ignore = NULL;
gkey.translate = NULL;
gkey.numeric = gkey.general_numeric = gkey.month = gkey.reverse = false;
gkey.skipsblanks = gkey.skipeblanks = false;
for (;;)
{
/* Parse an operand as a file after "--" was seen; */
if (c == -1 || ((c = getopt_long (argc, argv, short_options,
long_options, NULL)) == -1))
{
if (optind == argc)
usage (LOOK_SORT_FAILURE);
string = argv[optind++] ;
if (optind == argc)
break;
nfiles = 1 ;
file = argv[optind++];
break;
}
else switch (c)
{
case 'b':
case 'd':
case 'f':
case 'g':
case 'i':
case 'M':
case 'n':
case 'r':
{
char str[2];
str[0] = c;
str[1] = '\0';
set_ordering (str, &gkey, bl_both);
}
break;
case 'k':
build_key (optarg);
break;
case 'l':
lflag = 1 ;
break;
case 'o':
output_file = optarg;
break;
case 'B':
specify_line_size (optarg);
break;
case 't':
tab = optarg[0];
if (tab != TAB_DEFAULT && optarg[1])
{
/* Provoke with `look -txx'. Complain about
"multi-character tab" instead of "multibyte tab", so
that the diagnostic's wording does not need to be
changed once multibyte characters are supported. */
error (LOOK_SORT_FAILURE, 0, _("multi-character tab `%s'"),
optarg);
}
break;
case 'y':
/* Accept and ignore e.g. -y0 for compatibility with Solaris
2.x through Solaris 7. -y is marked as obsolete starting
with Solaris 8. */
break;
case 'z':
eolchar = 0;
break;
case_GETOPT_HELP_CHAR;
case_GETOPT_VERSION_CHAR (PROGRAM_NAME, AUTHORS);
default:
usage (LOOK_SORT_FAILURE);
}
}
if (nfiles == 0)
{
nfiles = 1;
file = dictionary ;
gkey.translate = fold_toupper ;
gkey.ignore = nondictionary ;
}
/* Inheritance of global options to individual keys. */
for (key = keylist; key; key = key->next)
if (!key->ignore && !key->translate && !key->skipsblanks && !key->reverse
&& !key->skipeblanks && !key->month && !key->numeric
&& !key->general_numeric)
{
key->ignore = gkey.ignore;
key->translate = gkey.translate;
key->skipsblanks = gkey.skipsblanks;
key->skipeblanks = gkey.skipeblanks;
key->month = gkey.month;
key->numeric = gkey.numeric;
key->general_numeric = gkey.general_numeric;
key->reverse = gkey.reverse;
}
reverse = gkey.reverse;
fflag = (gkey.translate == fold_toupper) ;
dflag = (gkey.ignore == nondictionary) ;
iflag = (gkey.ignore == nonprinting) ;
if (!keylist && (gkey.skipsblanks || gkey.skipeblanks || gkey.month
|| gkey.numeric || gkey.general_numeric))
insertkey (&gkey);
if (!keylist)
{
/* If there is no keylist, comparisons will be done using prefix
matching after considering -f and -d flags
*/
char *readp, *writep, ch ;
/* If there is a tab character, truncate the string at its first
appearance (including the tab character)
*/
if (tab != TAB_DEFAULT)
{
char *p ;
if ((p = strchr(string, tab)) != NULL)
*++p = '\0' ;
}
/* Reformat 'string' to avoid doing it multiple times later */
for (readp = writep = string; (ch = *readp++);)
{
if (fflag)
ch = fold_toupper[ch] ;
if (dflag && nondictionary[ch])
continue ;
if (iflag && nonprinting[ch])
continue ;
*(writep++) = ch ;
}
*writep = '\0' ;
}
struct line line ;
make_line (&line, string, string+strlen(string)) ;
binary_search(&line, file);
if (have_read_stdin && fclose (stdin) == EOF)
die (_("close failed"), "-");
exit (exit_status);
}
/* sort - sort lines of text (with all kinds of options).
Copyright (C) 1988, 1991-2005 Free Software Foundation, Inc.
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2, or (at your option)
any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software Foundation,
Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
Written December 1988 by Mike Haertel.
The author may be reached (Email) at the address address@hidden,
or (US mail) as Mike Haertel c/o Free Software Foundation.
Ãrn E. Hansen added NLS support in 1997. */
#include <config.h>
#include <getopt.h>
#include <sys/types.h>
#include <signal.h>
#include "system.h"
#include "error.h"
#include "hard-locale.h"
#include "inttostr.h"
#include "physmem.h"
#include "posixver.h"
#include "quote.h"
#include "stdlib--.h"
#include "stdio--.h"
#include "strnumcmp.h"
#include "xmemcoll.h"
#include "xstrtol.h"
#include "compare.h"
#if HAVE_SYS_RESOURCE_H
# include <sys/resource.h>
#endif
#ifndef RLIMIT_DATA
struct rlimit { size_t rlim_cur; };
# define getrlimit(Resource, Rlp) (-1)
#endif
/* The official name of this program (e.g., no `g' prefix). */
#define PROGRAM_NAME "sort"
#define AUTHORS "Mike Haertel", "Paul Eggert"
/* Use SA_NOCLDSTOP as a proxy for whether the sigaction machinery is
present. */
#ifndef SA_NOCLDSTOP
# define SA_NOCLDSTOP 0
# define sigprocmask(How, Set, Oset) /* empty */
# define sigset_t int
# if ! HAVE_SIGINTERRUPT
# define siginterrupt(sig, flag) /* empty */
# endif
#endif
#ifndef DEFAULT_TMPDIR
# define DEFAULT_TMPDIR "/tmp"
#endif
/* The name this program was run with. */
char *program_name;
/* During the merge phase, the number of files to merge at once. */
#define NMERGE 16
/* Minimum size for a merge or check buffer. */
#define MIN_MERGE_BUFFER_SIZE (2 + sizeof (struct line))
/* Minimum sort size; the code might not work with smaller sizes. */
#define MIN_SORT_SIZE (NMERGE * MIN_MERGE_BUFFER_SIZE)
/* The number of bytes needed for a merge or check buffer, which can
function relatively efficiently even if it holds only one line. If
a longer line is seen, this value is increased. */
static size_t merge_buffer_size = MAX (MIN_MERGE_BUFFER_SIZE, 256 * 1024);
/* The approximate maximum number of bytes of main memory to use, as
specified by the user. Zero if the user has not specified a size. */
static size_t sort_size;
/* The guessed size for non-regular files. */
#define INPUT_FILE_SIZE_GUESS (1024 * 1024)
/* Array of directory names in which any temporary files are to be created. */
static char const **temp_dirs;
/* Number of temporary directory names used. */
static size_t temp_dir_count;
/* Number of allocated slots in temp_dirs. */
static size_t temp_dir_alloc;
/* Flag to reverse the order of all comparisons. */
static bool reverse;
/* Flag for stable sort. This turns off the last ditch bytewise
comparison of lines, and instead leaves lines in the same order
they were read if all keys compare equal. */
static bool stable;
/* Flag to remove consecutive duplicate lines from the output.
Only the last of a sequence of equal lines will be output. */
static bool unique;
static void sortlines_temp (struct line *, size_t, struct line *);
void
usage (int status)
{
if (status != EXIT_SUCCESS)
fprintf (stderr, _("Try `%s --help' for more information.\n"),
program_name);
else
{
printf (_("\
Usage: %s [OPTION]... [FILE]...\n\
"),
program_name);
fputs (_("\
Write sorted concatenation of all FILE(s) to standard output.\n\
\n\
"), stdout);
fputs (_("\
Mandatory arguments to long options are mandatory for short options too.\n\
"), stdout);
fputs (_("\
Ordering options:\n\
\n\
"), stdout);
fputs (_("\
-b, --ignore-leading-blanks ignore leading blanks\n\
-d, --dictionary-order consider only blanks and alphanumeric
characters\n\
-f, --ignore-case fold lower case to upper case characters\n\
"), stdout);
fputs (_("\
-g, --general-numeric-sort compare according to general numerical value\n\
-i, --ignore-nonprinting consider only printable characters\n\
-M, --month-sort compare (unknown) < `JAN' < ... < `DEC'\n\
-n, --numeric-sort compare according to string numerical value\n\
-r, --reverse reverse the result of comparisons\n\
\n\
"), stdout);
fputs (_("\
Other options:\n\
\n\
-c, --check check whether input is sorted; do not sort\n\
-k, --key=POS1[,POS2] start a key at POS1, end it at POS 2 (origin 1)\n\
-m, --merge merge already sorted files; do not sort\n\
-o, --output=FILE write result to FILE instead of standard output\n\
-s, --stable stabilize sort by disabling last-resort
comparison\n\
-S, --buffer-size=SIZE use SIZE for main memory buffer\n\
"), stdout);
printf (_("\
-t, --field-separator=SEP use SEP instead of non-blank to blank transition\n\
-T, --temporary-directory=DIR use DIR for temporaries, not $TMPDIR or %s;\n\
multiple options specify multiple directories\n\
-u, --unique with -c, check for strict ordering;\n\
without -c, output only the first of an equal
run\n\
"), DEFAULT_TMPDIR);
fputs (_("\
-z, --zero-terminated end lines with 0 byte, not newline\n\
"), stdout);
fputs (HELP_OPTION_DESCRIPTION, stdout);
fputs (VERSION_OPTION_DESCRIPTION, stdout);
fputs (_("\
\n\
POS is F[.C][OPTS], where F is the field number and C the character position\n\
in the field. OPTS is one or more single-letter ordering options, which\n\
override global ordering options for that key. If no key is given, use the\n\
entire line as the key.\n\
\n\
SIZE may be followed by the following multiplicative suffixes:\n\
"), stdout);
fputs (_("\
% 1% of memory, b 1, K 1024 (default), and so on for M, G, T, P, E, Z, Y.\n\
\n\
With no FILE, or when FILE is -, read standard input.\n\
\n\
*** WARNING ***\n\
The locale specified by the environment affects sort order.\n\
Set LC_ALL=C to get the traditional sort order that uses\n\
native byte values.\n\
"), stdout );
printf (_("\nReport bugs to <%s>.\n"), PACKAGE_BUGREPORT);
}
exit (status);
}
static char const short_options[] = "-bcdfgik:mMno:rsS:t:T:uy:z";
static struct option const long_options[] =
{
{"ignore-leading-blanks", no_argument, NULL, 'b'},
{"check", no_argument, NULL, 'c'},
{"dictionary-order", no_argument, NULL, 'd'},
{"ignore-case", no_argument, NULL, 'f'},
{"general-numeric-sort", no_argument, NULL, 'g'},
{"ignore-nonprinting", no_argument, NULL, 'i'},
{"key", required_argument, NULL, 'k'},
{"merge", no_argument, NULL, 'm'},
{"month-sort", no_argument, NULL, 'M'},
{"numeric-sort", no_argument, NULL, 'n'},
{"output", required_argument, NULL, 'o'},
{"reverse", no_argument, NULL, 'r'},
{"stable", no_argument, NULL, 's'},
{"buffer-size", required_argument, NULL, 'S'},
{"field-separator", required_argument, NULL, 't'},
{"temporary-directory", required_argument, NULL, 'T'},
{"unique", no_argument, NULL, 'u'},
{"zero-terminated", no_argument, NULL, 'z'},
{GETOPT_HELP_OPTION_DECL},
{GETOPT_VERSION_OPTION_DECL},
{NULL, 0, NULL, 0},
};
/* The list of temporary files. */
struct tempnode
{
struct tempnode *volatile next;
char name[1]; /* Actual size is 1 + file name length. */
};
static struct tempnode *volatile temphead;
static struct tempnode *volatile *temptail = &temphead;
/* Clean up any remaining temporary files. */
static void
cleanup (void)
{
struct tempnode const *node;
for (node = temphead; node; node = node->next)
unlink (node->name);
}
/* Create a new temporary file, returning its newly allocated name.
Store into *PFP a stream open for writing. */
static char *
create_temp_file (FILE **pfp)
{
static char const slashbase[] = "/sortXXXXXX";
static size_t temp_dir_index;
sigset_t oldset;
int fd;
int saved_errno;
char const *temp_dir = temp_dirs[temp_dir_index];
size_t len = strlen (temp_dir);
struct tempnode *node =
xmalloc (offsetof (struct tempnode, name) + len + sizeof slashbase);
char *file = node->name;
memcpy (file, temp_dir, len);
memcpy (file + len, slashbase, sizeof slashbase);
node->next = NULL;
if (++temp_dir_index == temp_dir_count)
temp_dir_index = 0;
/* Create the temporary file in a critical section, to avoid races. */
sigprocmask (SIG_BLOCK, &caught_signals, &oldset);
fd = mkstemp (file);
if (0 <= fd)
{
*temptail = node;
temptail = &node->next;
}
saved_errno = errno;
sigprocmask (SIG_SETMASK, &oldset, NULL);
errno = saved_errno;
if (fd < 0 || (*pfp = fdopen (fd, "w")) == NULL)
die (_("cannot create temporary file"), file);
return file;
}
static void
write_bytes (const char *buf, size_t n_bytes, FILE *fp, const char *output_file)
{
if (fwrite (buf, 1, n_bytes, fp) != n_bytes)
die (_("write failed"), output_file);
}
/* Append DIR to the array of temporary directory names. */
static void
add_temp_dir (char const *dir)
{
if (temp_dir_count == temp_dir_alloc)
temp_dirs = x2nrealloc (temp_dirs, &temp_dir_alloc, sizeof *temp_dirs);
temp_dirs[temp_dir_count++] = dir;
}
/* Remove NAME from the list of temporary files. */
static void
zaptemp (const char *name)
{
struct tempnode *volatile *pnode;
struct tempnode *node;
struct tempnode *next;
sigset_t oldset;
int unlink_status;
int unlink_errno = 0;
for (pnode = &temphead; (node = *pnode)->name != name; pnode = &node->next)
continue;
/* Unlink the temporary file in a critical section to avoid races. */
next = node->next;
sigprocmask (SIG_BLOCK, &caught_signals, &oldset);
unlink_status = unlink (name);
unlink_errno = errno;
*pnode = next;
sigprocmask (SIG_SETMASK, &oldset, NULL);
if (unlink_status != 0)
error (0, unlink_errno, _("warning: cannot remove: %s"), name);
if (! next)
temptail = pnode;
free (node);
}
/* Specify the amount of main memory to use when sorting. */
static void
specify_sort_size (char const *s)
{
uintmax_t n;
char *suffix;
enum strtol_error e = xstrtoumax (s, &suffix, 10, &n, "EgGkKmMPtTYZ");
/* The default unit is KiB. */
if (e == LONGINT_OK && ISDIGIT (suffix[-1]))
{
if (n <= UINTMAX_MAX / 1024)
n *= 1024;
else
e = LONGINT_OVERFLOW;
}
/* A 'b' suffix means bytes; a '%' suffix means percent of memory. */
if (e == LONGINT_INVALID_SUFFIX_CHAR && ISDIGIT (suffix[-1]) && ! suffix[1])
switch (suffix[0])
{
case 'b':
e = LONGINT_OK;
break;
case '%':
{
double mem = physmem_total () * n / 100;
/* Use "<", not "<=", to avoid problems with rounding. */
if (mem < UINTMAX_MAX)
{
n = mem;
e = LONGINT_OK;
}
else
e = LONGINT_OVERFLOW;
}
break;
}
if (e == LONGINT_OK)
{
/* If multiple sort sizes are specified, take the maximum, so
that option order does not matter. */
if (n < sort_size)
return;
sort_size = n;
if (sort_size == n)
{
sort_size = MAX (sort_size, MIN_SORT_SIZE);
return;
}
e = LONGINT_OVERFLOW;
}
STRTOL_FATAL_ERROR (s, _("sort size"), e);
}
/* Return the default sort size. */
static size_t
default_sort_size (void)
{
/* Let MEM be available memory or 1/8 of total memory, whichever
is greater. */
double avail = physmem_available ();
double total = physmem_total ();
double mem = MAX (avail, total / 8);
struct rlimit rlimit;
/* Let SIZE be MEM, but no more than the maximum object size or
system resource limits. Avoid the MIN macro here, as it is not
quite right when only one argument is floating point. Don't
bother to check for values like RLIM_INFINITY since in practice
they are not much less than SIZE_MAX. */
size_t size = SIZE_MAX;
if (mem < size)
size = mem;
if (getrlimit (RLIMIT_DATA, &rlimit) == 0 && rlimit.rlim_cur < size)
size = rlimit.rlim_cur;
#ifdef RLIMIT_AS
if (getrlimit (RLIMIT_AS, &rlimit) == 0 && rlimit.rlim_cur < size)
size = rlimit.rlim_cur;
#endif
/* Leave a large safety margin for the above limits, as failure can
occur when they are exceeded. */
size /= 2;
#ifdef RLIMIT_RSS
/* Leave a 1/16 margin for RSS to leave room for code, stack, etc.
Exceeding RSS is not fatal, but can be quite slow. */
if (getrlimit (RLIMIT_RSS, &rlimit) == 0 && rlimit.rlim_cur / 16 * 15 < size)
size = rlimit.rlim_cur / 16 * 15;
#endif
/* Use no less than the minimum. */
return MAX (size, MIN_SORT_SIZE);
}
/* Return the sort buffer size to use with the input files identified
by FPS and FILES, which are alternate names of the same files.
NFILES gives the number of input files; NFPS may be less. Assume
that each input line requires LINE_BYTES extra bytes' worth of line
information. Do not exceed a bound on the size: if the bound is
not specified by the user, use a default. */
static size_t
sort_buffer_size (FILE *const *fps, size_t nfps,
char *const *files, size_t nfiles,
size_t line_bytes)
{
/* A bound on the input size. If zero, the bound hasn't been
determined yet. */
static size_t size_bound;
/* In the worst case, each input byte is a newline. */
size_t worst_case_per_input_byte = line_bytes + 1;
/* Keep enough room for one extra input line and an extra byte.
This extra room might be needed when preparing to read EOF. */
size_t size = worst_case_per_input_byte + 1;
size_t i;
for (i = 0; i < nfiles; i++)
{
struct stat st;
off_t file_size;
size_t worst_case;
if ((i < nfps ? fstat (fileno (fps[i]), &st)
: STREQ (files[i], "-") ? fstat (STDIN_FILENO, &st)
: stat (files[i], &st))
!= 0)
die (_("stat failed"), files[i]);
if (S_ISREG (st.st_mode))
file_size = st.st_size;
else
{
/* The file has unknown size. If the user specified a sort
buffer size, use that; otherwise, guess the size. */
if (sort_size)
return sort_size;
file_size = INPUT_FILE_SIZE_GUESS;
}
if (! size_bound)
{
size_bound = sort_size;
if (! size_bound)
size_bound = default_sort_size ();
}
/* Add the amount of memory needed to represent the worst case
where the input consists entirely of newlines followed by a
single non-newline. Check for overflow. */
worst_case = file_size * worst_case_per_input_byte + 1;
if (file_size != worst_case / worst_case_per_input_byte
|| size_bound - size <= worst_case)
return size_bound;
size += worst_case;
}
return size;
}
/* Initialize BUF. Reserve LINE_BYTES bytes for each line; LINE_BYTES
must be at least sizeof (struct line). Allocate ALLOC bytes
initially. */
static void
initbuf (struct buffer *buf, size_t line_bytes, size_t alloc)
{
/* Ensure that the line array is properly aligned. If the desired
size cannot be allocated, repeatedly halve it until allocation
succeeds. The smaller allocation may hurt overall performance,
but that's better than failing. */
for (;;)
{
alloc += sizeof (struct line) - alloc % sizeof (struct line);
buf->buf = malloc (alloc);
if (buf->buf)
break;
alloc /= 2;
if (alloc <= line_bytes + 1)
xalloc_die ();
}
buf->line_bytes = line_bytes;
buf->alloc = alloc;
buf->used = buf->left = buf->nlines = 0;
buf->eof = false;
}
/* Return one past the limit of the line array. */
static inline struct line *
buffer_linelim (struct buffer const *buf)
{
return (struct line *) (buf->buf + buf->alloc);
}
/* Fill BUF reading from FP, moving buf->left bytes from the end
of buf->buf to the beginning first. If EOF is reached and the
file wasn't terminated by a newline, supply one. Set up BUF's line
table too. FILE is the name of the file corresponding to FP.
Return true if some input was read. */
static bool
fillbuf (struct buffer *buf, FILE *fp, char const *file)
{
struct keyfield const *key = keylist;
char eol = eolchar;
size_t line_bytes = buf->line_bytes;
size_t mergesize = merge_buffer_size - MIN_MERGE_BUFFER_SIZE;
if (buf->eof)
return false;
if (buf->used != buf->left)
{
memmove (buf->buf, buf->buf + buf->used - buf->left, buf->left);
buf->used = buf->left;
buf->nlines = 0;
}
for (;;)
{
char *ptr = buf->buf + buf->used;
struct line *linelim = buffer_linelim (buf);
struct line *line = linelim - buf->nlines;
size_t avail = (char *) linelim - buf->nlines * line_bytes - ptr;
char *line_start = buf->nlines ? line->text + line->length : buf->buf;
while (line_bytes + 1 < avail)
{
/* Read as many bytes as possible, but do not read so many
bytes that there might not be enough room for the
corresponding line array. The worst case is when the
rest of the input file consists entirely of newlines,
except that the last byte is not a newline. */
size_t readsize = (avail - 1) / (line_bytes + 1);
size_t bytes_read = fread (ptr, 1, readsize, fp);
char *ptrlim = ptr + bytes_read;
char *p;
avail -= bytes_read;
if (bytes_read != readsize)
{
if (ferror (fp))
die (_("read failed"), file);
if (feof (fp))
{
buf->eof = true;
if (buf->buf == ptrlim)
return false;
if (ptrlim[-1] != eol)
*ptrlim++ = eol;
}
}
/* Find and record each line in the just-read input. */
while ((p = memchr (ptr, eol, ptrlim - ptr)))
{
ptr = p + 1;
line--;
line->text = line_start;
line->length = ptr - line_start;
mergesize = MAX (mergesize, line->length);
avail -= line_bytes;
if (key)
{
/* Precompute the position of the first key for
efficiency. */
line->keylim = (key->eword == SIZE_MAX
? p
: limfield (line, key));
if (key->sword != SIZE_MAX)
line->keybeg = begfield (line, key);
else
{
if (key->skipsblanks)
while (blanks[to_uchar (*line_start)])
line_start++;
line->keybeg = line_start;
}
}
line_start = ptr;
}
ptr = ptrlim;
if (buf->eof)
break;
}
buf->used = ptr - buf->buf;
buf->nlines = buffer_linelim (buf) - line;
if (buf->nlines != 0)
{
buf->left = ptr - line_start;
merge_buffer_size = mergesize + MIN_MERGE_BUFFER_SIZE;
return true;
}
/* The current input line is too long to fit in the buffer.
Double the buffer size and try again. */
buf->buf = X2REALLOC (buf->buf, &buf->alloc);
}
}
/* Compare two lines A and B, returning negative, zero, or positive
depending on whether A compares less than, equal to, or greater than B. */
static int
compare (const struct line *a, const struct line *b)
{
int diff;
size_t alen, blen;
/* First try to compare on the specified keys (if any).
The only two cases with no key at all are unadorned sort,
and unadorned sort -r. */
if (keylist)
{
diff = keycompare (a, b);
if (diff | unique | stable)
return diff;
}
/* If the keys all compare equal (or no keys were specified)
fall through to the default comparison. */
alen = a->length - 1, blen = b->length - 1;
if (alen == 0)
diff = - NONZERO (blen);
else if (blen == 0)
diff = 1;
else if (hard_LC_COLLATE)
diff = xmemcoll (a->text, alen, b->text, blen);
else if (! (diff = memcmp (a->text, b->text, MIN (alen, blen))))
diff = alen < blen ? -1 : alen != blen;
return reverse ? -diff : diff;
}
/* Check that the lines read from FILE_NAME come in order. Print a
diagnostic (FILE_NAME, line number, contents of line) to stderr and return
false if they are not in order. Otherwise, print no diagnostic
and return true. */
static bool
check (char const *file_name)
{
FILE *fp = xfopen (file_name, "r");
struct buffer buf; /* Input buffer. */
struct line temp; /* Copy of previous line. */
size_t alloc = 0;
uintmax_t line_number = 0;
struct keyfield const *key = keylist;
bool nonunique = ! unique;
bool ordered = true;
initbuf (&buf, sizeof (struct line),
MAX (merge_buffer_size, sort_size));
temp.text = NULL;
while (fillbuf (&buf, fp, file_name))
{
struct line const *line = buffer_linelim (&buf);
struct line const *linebase = line - buf.nlines;
/* Make sure the line saved from the old buffer contents is
less than or equal to the first line of the new buffer. */
if (alloc && nonunique <= compare (&temp, line - 1))
{
found_disorder:
{
struct line const *disorder_line = line - 1;
uintmax_t disorder_line_number =
buffer_linelim (&buf) - disorder_line + line_number;
char hr_buf[INT_BUFSIZE_BOUND (uintmax_t)];
fprintf (stderr, _("%s: %s:%s: disorder: "),
program_name, file_name,
umaxtostr (disorder_line_number, hr_buf));
write_bytes (disorder_line->text, disorder_line->length, stderr,
_("standard error"));
ordered = false;
break;
}
}
/* Compare each line in the buffer with its successor. */
while (linebase < --line)
if (nonunique <= compare (line, line - 1))
goto found_disorder;
line_number += buf.nlines;
/* Save the last line of the buffer. */
if (alloc < line->length)
{
do
{
alloc *= 2;
if (! alloc)
{
alloc = line->length;
break;
}
}
while (alloc < line->length);
temp.text = xrealloc (temp.text, alloc);
}
memcpy (temp.text, line->text, line->length);
temp.length = line->length;
if (key)
{
temp.keybeg = temp.text + (line->keybeg - line->text);
temp.keylim = temp.text + (line->keylim - line->text);
}
}
xfclose (fp, file_name);
free (buf.buf);
free (temp.text);
return ordered;
}
/* Merge lines from FILES onto OFP. NTEMPS is the number of temporary
files (all of which are at the start of the FILES array), and
NFILES is the number of files; 0 <= NTEMPS <= NFILES <= NMERGE.
Close input and output files before returning.
OUTPUT_FILE gives the name of the output file. If it is NULL,
the output file is standard output. If OFP is NULL, the output
file has not been opened yet (or written to, if standard output). */
static void
mergefps (char **files, size_t ntemps, size_t nfiles,
FILE *ofp, char const *output_file)
{
FILE *fps[NMERGE]; /* Input streams for each file. */
struct buffer buffer[NMERGE]; /* Input buffers for each file. */
struct line saved; /* Saved line storage for unique check. */
struct line const *savedline = NULL;
/* &saved if there is a saved line. */
size_t savealloc = 0; /* Size allocated for the saved line. */
struct line const *cur[NMERGE]; /* Current line in each line table. */
struct line const *base[NMERGE]; /* Base of each line table. */
size_t ord[NMERGE]; /* Table representing a permutation of fps,
such that cur[ord[0]] is the smallest line
and will be next output. */
size_t i;
size_t j;
size_t t;
struct keyfield const *key = keylist;
saved.text = NULL;
/* Read initial lines from each input file. */
for (i = 0; i < nfiles; )
{
fps[i] = xfopen (files[i], "r");
initbuf (&buffer[i], sizeof (struct line),
MAX (merge_buffer_size, sort_size / nfiles));
if (fillbuf (&buffer[i], fps[i], files[i]))
{
struct line const *linelim = buffer_linelim (&buffer[i]);
cur[i] = linelim - 1;
base[i] = linelim - buffer[i].nlines;
i++;
}
else
{
/* fps[i] is empty; eliminate it from future consideration. */
xfclose (fps[i], files[i]);
if (i < ntemps)
{
ntemps--;
zaptemp (files[i]);
}
free (buffer[i].buf);
--nfiles;
for (j = i; j < nfiles; ++j)
files[j] = files[j + 1];
}
}
if (! ofp)
ofp = xfopen (output_file, "w");
/* Set up the ord table according to comparisons among input lines.
Since this only reorders two items if one is strictly greater than
the other, it is stable. */
for (i = 0; i < nfiles; ++i)
ord[i] = i;
for (i = 1; i < nfiles; ++i)
if (0 < compare (cur[ord[i - 1]], cur[ord[i]]))
t = ord[i - 1], ord[i - 1] = ord[i], ord[i] = t, i = 0;
/* Repeatedly output the smallest line until no input remains. */
while (nfiles)
{
struct line const *smallest = cur[ord[0]];
/* If uniquified output is turned on, output only the first of
an identical series of lines. */
if (unique)
{
if (savedline && compare (savedline, smallest))
{
savedline = NULL;
write_bytes (saved.text, saved.length, ofp, output_file);
}
if (!savedline)
{
savedline = &saved;
if (savealloc < smallest->length)
{
do
if (! savealloc)
{
savealloc = smallest->length;
break;
}
while ((savealloc *= 2) < smallest->length);
saved.text = xrealloc (saved.text, savealloc);
}
saved.length = smallest->length;
memcpy (saved.text, smallest->text, saved.length);
if (key)
{
saved.keybeg =
saved.text + (smallest->keybeg - smallest->text);
saved.keylim =
saved.text + (smallest->keylim - smallest->text);
}
}
}
else
write_bytes (smallest->text, smallest->length, ofp, output_file);
/* Check if we need to read more lines into core. */
if (base[ord[0]] < smallest)
cur[ord[0]] = smallest - 1;
else
{
if (fillbuf (&buffer[ord[0]], fps[ord[0]], files[ord[0]]))
{
struct line const *linelim = buffer_linelim (&buffer[ord[0]]);
cur[ord[0]] = linelim - 1;
base[ord[0]] = linelim - buffer[ord[0]].nlines;
}
else
{
/* We reached EOF on fps[ord[0]]. */
for (i = 1; i < nfiles; ++i)
if (ord[i] > ord[0])
--ord[i];
--nfiles;
xfclose (fps[ord[0]], files[ord[0]]);
if (ord[0] < ntemps)
{
ntemps--;
zaptemp (files[ord[0]]);
}
free (buffer[ord[0]].buf);
for (i = ord[0]; i < nfiles; ++i)
{
fps[i] = fps[i + 1];
files[i] = files[i + 1];
buffer[i] = buffer[i + 1];
cur[i] = cur[i + 1];
base[i] = base[i + 1];
}
for (i = 0; i < nfiles; ++i)
ord[i] = ord[i + 1];
continue;
}
}
/* The new line just read in may be larger than other lines
already in main memory; push it back in the queue until we
encounter a line larger than it. Optimize for the common
case where the new line is smallest. */
{
size_t lo = 1;
size_t hi = nfiles;
size_t probe = lo;
size_t ord0 = ord[0];
size_t count_of_smaller_lines;
while (lo < hi)
{
int cmp = compare (cur[ord0], cur[ord[probe]]);
if (cmp < 0 || (cmp == 0 && ord0 < ord[probe]))
hi = probe;
else
lo = probe + 1;
probe = (lo + hi) / 2;
}
count_of_smaller_lines = lo - 1;
for (j = 0; j < count_of_smaller_lines; j++)
ord[j] = ord[j + 1];
ord[count_of_smaller_lines] = ord0;
}
}
if (unique && savedline)
{
write_bytes (saved.text, saved.length, ofp, output_file);
free (saved.text);
}
xfclose (ofp, output_file);
}
/* Merge into T the two sorted arrays of lines LO (with NLO members)
and HI (with NHI members). T, LO, and HI point just past their
respective arrays, and the arrays are in reverse order. NLO and
NHI must be positive, and HI - NHI must equal T - (NLO + NHI). */
static inline void
mergelines (struct line *t,
struct line const *lo, size_t nlo,
struct line const *hi, size_t nhi)
{
for (;;)
if (compare (lo - 1, hi - 1) <= 0)
{
*--t = *--lo;
if (! --nlo)
{
/* HI - NHI equalled T - (NLO + NHI) when this function
began. Therefore HI must equal T now, and there is no
need to copy from HI to T. */
return;
}
}
else
{
*--t = *--hi;
if (! --nhi)
{
do
*--t = *--lo;
while (--nlo);
return;
}
}
}
/* Sort the array LINES with NLINES members, using TEMP for temporary space.
NLINES must be at least 2.
The input and output arrays are in reverse order, and LINES and
TEMP point just past the end of their respective arrays.
Use a recursive divide-and-conquer algorithm, in the style
suggested by Knuth volume 3 (2nd edition), exercise 5.2.4-23. Use
the optimization suggested by exercise 5.2.4-10; this requires room
for only 1.5*N lines, rather than the usual 2*N lines. Knuth
writes that this memory optimization was originally published by
D. A. Bell, Comp J. 1 (1958), 75. */
static void
sortlines (struct line *lines, size_t nlines, struct line *temp)
{
if (nlines == 2)
{
if (0 < compare (&lines[-1], &lines[-2]))
{
struct line tmp = lines[-1];
lines[-1] = lines[-2];
lines[-2] = tmp;
}
}
else
{
size_t nlo = nlines / 2;
size_t nhi = nlines - nlo;
struct line *lo = lines;
struct line *hi = lines - nlo;
struct line *sorted_lo = temp;
sortlines (hi, nhi, temp);
if (1 < nlo)
sortlines_temp (lo, nlo, sorted_lo);
else
sorted_lo[-1] = lo[-1];
mergelines (lines, sorted_lo, nlo, hi, nhi);
}
}
/* Like sortlines (LINES, NLINES, TEMP), except output into TEMP
rather than sorting in place. */
static void
sortlines_temp (struct line *lines, size_t nlines, struct line *temp)
{
if (nlines == 2)
{
bool swap = (0 < compare (&lines[-1], &lines[-2]));
temp[-1] = lines[-1 - swap];
temp[-2] = lines[-2 + swap];
}
else
{
size_t nlo = nlines / 2;
size_t nhi = nlines - nlo;
struct line *lo = lines;
struct line *hi = lines - nlo;
struct line *sorted_hi = temp - nlo;
sortlines_temp (hi, nhi, sorted_hi);
if (1 < nlo)
sortlines (lo, nlo, temp);
mergelines (temp, lo, nlo, sorted_hi, nhi);
}
}
/* Scan through FILES[NTEMPS .. NFILES-1] looking for a file that is
the same as OUTFILE. If found, merge the found instances (and perhaps
some other files) into a temporary file so that it can in turn be
merged into OUTFILE without destroying OUTFILE before it is completely
read. Return the new value of NFILES, which differs from the old if
some merging occurred.
This test ensures that an otherwise-erroneous use like
"sort -m -o FILE ... FILE ..." copies FILE before writing to it.
It's not clear that POSIX requires this nicety.
Detect common error cases, but don't try to catch obscure cases like
"cat ... FILE ... | sort -m -o FILE"
where traditional "sort" doesn't copy the input and where
people should know that they're getting into trouble anyway.
Catching these obscure cases would slow down performance in
common cases. */
static size_t
avoid_trashing_input (char **files, size_t ntemps, size_t nfiles,
char const *outfile)
{
size_t i;
bool got_outstat = false;
struct stat outstat;
for (i = ntemps; i < nfiles; i++)
{
bool is_stdin = STREQ (files[i], "-");
bool same;
struct stat instat;
if (outfile && STREQ (outfile, files[i]) && !is_stdin)
same = true;
else
{
if (! got_outstat)
{
if ((outfile
? stat (outfile, &outstat)
: fstat (STDOUT_FILENO, &outstat))
!= 0)
break;
got_outstat = true;
}
same = (((is_stdin
? fstat (STDIN_FILENO, &instat)
: stat (files[i], &instat))
== 0)
&& SAME_INODE (instat, outstat));
}
if (same)
{
FILE *tftp;
char *temp = create_temp_file (&tftp);
mergefps (&files[i], 0, nfiles - i, tftp, temp);
files[i] = temp;
return i + 1;
}
}
return nfiles;
}
/* Merge the input FILES. NTEMPS is the number of files at the
start of FILES that are temporary; it is zero at the top level.
NFILES is the total number of files. Put the output in
OUTPUT_FILE; a null OUTPUT_FILE stands for standard output. */
static void
merge (char **files, size_t ntemps, size_t nfiles, char const *output_file)
{
while (NMERGE < nfiles)
{
/* Number of input files processed so far. */
size_t in;
/* Number of output files generated so far. */
size_t out;
/* nfiles % NMERGE; this counts input files that are left over
after all full-sized merges have been done. */
size_t remainder;
/* Number of easily-available slots at the next loop iteration. */
size_t cheap_slots;
/* Do as many NMERGE-size merges as possible. */
for (out = in = 0; out < nfiles / NMERGE; out++, in += NMERGE)
{
FILE *tfp;
char *temp = create_temp_file (&tfp);
size_t nt = MIN (ntemps, NMERGE);
ntemps -= nt;
mergefps (&files[in], nt, NMERGE, tfp, temp);
files[out] = temp;
}
remainder = nfiles - in;
cheap_slots = NMERGE - out % NMERGE;
if (cheap_slots < remainder)
{
/* So many files remain that they can't all be put into the last
NMERGE-sized output window. Do one more merge. Merge as few
files as possible, to avoid needless I/O. */
size_t nshortmerge = remainder - cheap_slots + 1;
FILE *tfp;
char *temp = create_temp_file (&tfp);
size_t nt = MIN (ntemps, nshortmerge);
ntemps -= nt;
mergefps (&files[in], nt, nshortmerge, tfp, temp);
files[out++] = temp;
in += nshortmerge;
}
/* Put the remaining input files into the last NMERGE-sized output
window, so they will be merged in the next pass. */
memmove(&files[out], &files[in], (nfiles - in) * sizeof *files);
ntemps += out;
nfiles -= in - out;
}
nfiles = avoid_trashing_input (files, ntemps, nfiles, output_file);
mergefps (files, ntemps, nfiles, NULL, output_file);
}
/* Sort NFILES FILES onto OUTPUT_FILE. */
static void
sort (char * const *files, size_t nfiles, char const *output_file)
{
struct buffer buf;
size_t ntemps = 0;
bool output_file_created = false;
buf.alloc = 0;
while (nfiles)
{
char const *temp_output;
char const *file = *files;
FILE *fp = xfopen (file, "r");
FILE *tfp;
size_t bytes_per_line = (2 * sizeof (struct line)
- sizeof (struct line) / 2);
if (! buf.alloc)
initbuf (&buf, bytes_per_line,
sort_buffer_size (&fp, 1, files, nfiles, bytes_per_line));
buf.eof = false;
files++;
nfiles--;
while (fillbuf (&buf, fp, file))
{
struct line *line;
struct line *linebase;
if (buf.eof && nfiles
&& (bytes_per_line + 1
< (buf.alloc - buf.used - bytes_per_line * buf.nlines)))
{
/* End of file, but there is more input and buffer room.
Concatenate the next input file; this is faster in
the usual case. */
buf.left = buf.used;
break;
}
line = buffer_linelim (&buf);
linebase = line - buf.nlines;
if (1 < buf.nlines)
sortlines (line, buf.nlines, linebase);
if (buf.eof && !nfiles && !ntemps && !buf.left)
{
xfclose (fp, file);
tfp = xfopen (output_file, "w");
temp_output = output_file;
output_file_created = true;
}
else
{
++ntemps;
temp_output = create_temp_file (&tfp);
}
do
{
line--;
write_bytes (line->text, line->length, tfp, temp_output);
if (unique)
while (linebase < line && compare (line, line - 1) == 0)
line--;
}
while (linebase < line);
xfclose (tfp, temp_output);
if (output_file_created)
goto finish;
}
xfclose (fp, file);
}
finish:
free (buf.buf);
if (! output_file_created)
{
size_t i;
struct tempnode *node = temphead;
char **tempfiles = xnmalloc (ntemps, sizeof *tempfiles);
for (i = 0; node; i++)
{
tempfiles[i] = node->name;
node = node->next;
}
merge (tempfiles, ntemps, ntemps, output_file);
free (tempfiles);
}
}
/* Handle interrupts and hangups. */
static void
sighandler (int sig)
{
if (! SA_NOCLDSTOP)
signal (sig, SIG_IGN);
cleanup ();
signal (sig, SIG_DFL);
raise (sig);
}
int
main (int argc, char **argv)
{
struct keyfield *key;
struct keyfield gkey;
char const *s;
int c = 0;
bool checkonly = false;
bool mergeonly = false;
size_t nfiles = 0;
bool posixly_correct = (getenv ("POSIXLY_CORRECT") != NULL);
bool obsolete_usage = (posix2_version () < 200112);
char *minus = "-", **files;
char const *outfile = NULL;
initialize_main (&argc, &argv);
program_name = argv[0];
setlocale (LC_ALL, "");
bindtextdomain (PACKAGE, LOCALEDIR);
textdomain (PACKAGE);
atexit (cleanup);
initialize_exit_failure (LOOK_SORT_FAILURE);
atexit (close_stdout);
hard_LC_COLLATE = hard_locale (LC_COLLATE);
#if HAVE_NL_LANGINFO
hard_LC_TIME = hard_locale (LC_TIME);
#endif
init_locale_decimal_point ();
have_read_stdin = false;
inittables ();
{
size_t i;
static int const sig[] = { SIGHUP, SIGINT, SIGPIPE, SIGTERM };
enum { nsigs = sizeof sig / sizeof sig[0] };
#if SA_NOCLDSTOP
struct sigaction act;
sigemptyset (&caught_signals);
for (i = 0; i < nsigs; i++)
{
sigaction (sig[i], NULL, &act);
if (act.sa_handler != SIG_IGN)
sigaddset (&caught_signals, sig[i]);
}
act.sa_handler = sighandler;
act.sa_mask = caught_signals;
act.sa_flags = 0;
for (i = 0; i < nsigs; i++)
if (sigismember (&caught_signals, sig[i]))
sigaction (sig[i], &act, NULL);
#else
for (i = 0; i < nsigs; i++)
if (signal (sig[i], SIG_IGN) != SIG_IGN)
{
signal (sig[i], sighandler);
siginterrupt (sig[i], 1);
}
#endif
}
gkey.sword = gkey.eword = SIZE_MAX;
gkey.ignore = NULL;
gkey.translate = NULL;
gkey.numeric = gkey.general_numeric = gkey.month = gkey.reverse = false;
gkey.skipsblanks = gkey.skipeblanks = false;
files = xnmalloc (argc, sizeof *files);
for (;;)
{
/* Parse an operand as a file after "--" was seen; or if
pedantic and a file was seen, unless the POSIX version
predates 1003.1-2001 and -c was not seen and the operand is
"-o FILE" or "-oFILE". */
if (c == -1
|| (posixly_correct && nfiles != 0
&& ! (obsolete_usage
&& ! checkonly
&& optind != argc
&& argv[optind][0] == '-' && argv[optind][1] == 'o'
&& (argv[optind][2] || optind + 1 != argc)))
|| ((c = getopt_long (argc, argv, short_options,
long_options, NULL))
== -1))
{
if (argc <= optind)
break;
files[nfiles++] = argv[optind++];
}
else switch (c)
{
case 1:
key = NULL;
if (obsolete_usage && optarg[0] == '+')
{
/* Treat +POS1 [-POS2] as a key if possible; but silently
treat an operand as a file if it is not a valid +POS1. */
key = new_key ();
s = parse_field_count (optarg + 1, &key->sword, NULL);
if (s && *s == '.')
s = parse_field_count (s + 1, &key->schar, NULL);
if (! (key->sword | key->schar))
key->sword = SIZE_MAX;
if (! s || *set_ordering (s, key, bl_start))
{
free (key);
key = NULL;
}
else
{
if (optind != argc && argv[optind][0] == '-'
&& ISDIGIT (argv[optind][1]))
{
char const *optarg1 = argv[optind++];
s = parse_field_count (optarg1 + 1, &key->eword,
N_("invalid number after `-'"));
if (*s == '.')
s = parse_field_count (s + 1, &key->echar,
N_("invalid number after `.'"));
if (*set_ordering (s, key, bl_end))
badfieldspec (optarg1,
N_("stray character in field spec"));
}
insertkey (key);
}
}
if (! key)
files[nfiles++] = optarg;
break;
case 'b':
case 'd':
case 'f':
case 'g':
case 'i':
case 'M':
case 'n':
case 'r':
{
char str[2];
str[0] = c;
str[1] = '\0';
set_ordering (str, &gkey, bl_both);
}
break;
case 'c':
checkonly = true;
break;
case 'k':
build_key (optarg) ;
break;
case 'm':
mergeonly = true;
break;
case 'o':
if (outfile && !STREQ (outfile, optarg))
error (LOOK_SORT_FAILURE, 0, _("multiple output files specified"));
outfile = optarg;
break;
case 's':
stable = true;
break;
case 'S':
specify_sort_size (optarg);
break;
case 't':
{
char newtab = optarg[0];
if (! newtab)
error (LOOK_SORT_FAILURE, 0, _("empty tab"));
if (optarg[1])
{
if (STREQ (optarg, "\\0"))
newtab = '\0';
else
{
/* Provoke with `sort -txx'. Complain about
"multi-character tab" instead of "multibyte tab", so
that the diagnostic's wording does not need to be
changed once multibyte characters are supported. */
error (LOOK_SORT_FAILURE, 0, _("multi-character tab %s"),
quote (optarg));
}
}
if (tab != TAB_DEFAULT && tab != newtab)
error (LOOK_SORT_FAILURE, 0, _("incompatible tabs"));
tab = newtab;
}
break;
case 'T':
add_temp_dir (optarg);
break;
case 'u':
unique = true;
break;
case 'y':
/* Accept and ignore e.g. -y0 for compatibility with Solaris 2.x
through Solaris 7. It is also accepted by many non-Solaris
"sort" implementations, e.g., AIX 5.2, HP-UX 11i v2, IRIX 6.5.
-y is marked as obsolete starting with Solaris 8 (1999), but is
still accepted as of Solaris 10 prerelease (2004).
Solaris 2.5.1 "sort -y 100" reads the input file "100", but
emulate Solaris 8 and 9 "sort -y 100" which ignores the "100",
and which in general ignores the argument after "-y" if it
consists entirely of digits (it can even be empty). */
if (optarg == argv[optind - 1])
{
char const *p;
for (p = optarg; ISDIGIT (*p); p++)
continue;
optind -= (*p != '\0');
}
break;
case 'z':
eolchar = 0;
break;
case_GETOPT_HELP_CHAR;
case_GETOPT_VERSION_CHAR (PROGRAM_NAME, AUTHORS);
default:
usage (LOOK_SORT_FAILURE);
}
}
/* Inheritance of global options to individual keys. */
for (key = keylist; key; key = key->next)
if (! (key->ignore || key->translate
|| (key->skipsblanks | key->reverse
| key->skipeblanks | key->month | key->numeric
| key->general_numeric)))
{
key->ignore = gkey.ignore;
key->translate = gkey.translate;
key->skipsblanks = gkey.skipsblanks;
key->skipeblanks = gkey.skipeblanks;
key->month = gkey.month;
key->numeric = gkey.numeric;
key->general_numeric = gkey.general_numeric;
key->reverse = gkey.reverse;
}
if (!keylist && (gkey.ignore || gkey.translate
|| (gkey.skipsblanks | gkey.skipeblanks | gkey.month
| gkey.numeric | gkey.general_numeric)))
insertkey (&gkey);
reverse = gkey.reverse;
if (temp_dir_count == 0)
{
char const *tmp_dir = getenv ("TMPDIR");
add_temp_dir (tmp_dir ? tmp_dir : DEFAULT_TMPDIR);
}
if (nfiles == 0)
{
nfiles = 1;
files = −
}
if (checkonly)
{
if (nfiles > 1)
{
error (0, 0, _("extra operand %s not allowed with -c"),
quote (files[1]));
usage (LOOK_SORT_FAILURE);
}
/* POSIX requires that sort return 1 IFF invoked with -c and the
input is not properly sorted. */
exit (check (files[0]) ? EXIT_SUCCESS : SORT_OUT_OF_ORDER);
}
if (mergeonly)
merge (files, 0, nfiles, outfile);
else
sort (files, nfiles, outfile);
if (have_read_stdin && fclose (stdin) == EOF)
die (_("close failed"), "-");
exit (EXIT_SUCCESS);
}
- Re: bsearch utility, (continued)
- Re: bsearch utility, James Youngman, 2005/07/14
- Re: bsearch utility, Paul Eggert, 2005/07/14
- Re: bsearch utility, Sorav Bansal, 2005/07/21
- Re: bsearch utility, Paul Eggert, 2005/07/21
- Re: bsearch utility, Sorav Bansal, 2005/07/22
- Re: bsearch utility, Paul Eggert, 2005/07/23
- Re: bsearch utility,
Sorav Bansal <=
Re: bsearch utility, Bob Proulx, 2005/07/14
Re: bsearch utility, Sorav Bansal, 2005/07/14