[Groff] character width in font files

[Daiki Ueno]

Hi,

It is suggested that the width of each character should be adjusted in
font files (font/devutf8/NOTES).

However, since the width of some Unicode character may differ under
different locale settings, I wonder if font files are really sufficient
for every user.

The attached is a patch to compute character width on the fly.

The patch is currently useless with the trunk, but with Colin Walters'
charclass branch I confirmed that it renders Japanese man pages with the
kinsoku shori applied correctly (er, mostly, it looks some kind of
hyphenation is necessary for non-punct Japanese characters):

http://ueno.fedorapeople.org/groff/kinsoku.png

=== modified file 'configure.ac'
--- configure.ac        2009-06-25 16:37:53 +0000
+++ configure.ac        2010-07-29 03:43:11 +0000
@@ -77,7 +77,8 @@
 
 # checks for headers
 AC_CHECK_HEADERS([stddef.h stdlib.h unistd.h dirent.h limits.h sys/dir.h \
-                  string.h strings.h math.h sys/time.h direct.h process.h])
+                  string.h strings.h math.h sys/time.h direct.h process.h \
+                  wchar.h])
 GROFF_ISC_SYSV3
 GROFF_POSIX
 
@@ -128,7 +129,7 @@
 # vsnprintf is in the same source file as snprintf
 AC_CHECK_FUNCS([vsnprintf], [], [AC_LIBOBJ([snprintf])])
 LIBS="$saved_libs"
-AC_CHECK_FUNCS([gettimeofday isatty kill rename setlocale strsep])
+AC_CHECK_FUNCS([gettimeofday isatty kill rename setlocale strsep wcwidth])
 GROFF_MKSTEMP
 AC_CHECK_DECLS([sys_siglist, getc_unlocked])
 AM_LANGINFO_CODESET

=== modified file 'src/devices/grotty/tty.cpp'
--- src/devices/grotty/tty.cpp  2010-05-23 05:09:00 +0000
+++ src/devices/grotty/tty.cpp  2010-07-29 03:43:11 +0000
@@ -877,6 +877,7 @@
     { "version", no_argument, 0, 'v' },
     { NULL, 0, 0, 0 }
   };
+  setlocale(LC_CTYPE, "");
   while ((c = getopt_long(argc, argv, "bBcdfF:hiI:oruUv", long_options, NULL))
         != EOF)
     switch(c) {

=== modified file 'src/include/lib.h'
--- src/include/lib.h   2009-06-25 16:37:53 +0000
+++ src/include/lib.h   2010-07-29 03:43:11 +0000
@@ -48,6 +48,13 @@
 #define getlocale(category) ((void)(category), (char *)"C")
 #endif /* !HAVE_SETLOCALE */
 
+#ifdef HAVE_WCWIDTH
+#include <wchar.h>
+#else
+typedef int wchar_t;
+#define wcwidth(c) ((wchar_t)-1)
+#endif
+
 char *strsave(const char *s);
 int is_prime(unsigned);
 double groff_hypot(double, double);

=== modified file 'src/libs/libgroff/font.cpp'
--- src/libs/libgroff/font.cpp  2009-01-05 20:10:29 +0000
+++ src/libs/libgroff/font.cpp  2010-07-29 03:43:11 +0000
@@ -376,6 +376,9 @@
     int width = 24;    // value found in the original font files
                        // XXX: this must be eventually moved back to the
                        //      font description file!
+    int w = wcwidth(get_code(g));
+    if (w > 0)
+      width *= w;
     if (real_size == unitwidth || font::unscaled_charwidths)
       return width;
     else
@@ -995,6 +998,11 @@
              t.error("bad code `%1' for character `%2'", p, nm);
              return 0;
            }
+           // XXX: this could be moved to font files, as suggested in
+           // font/devutf8/NOTE.
+           int w = wcwidth(metric.code);
+           if (w > 0)
+             metric.width *= w;
            p = strtok(0, WS);
            if ((p == NULL) || (strcmp(p, "--") == 0)) {
              metric.special_device_coding = NULL;

=== modified file 'src/roff/troff/input.cpp'
--- src/roff/troff/input.cpp    2009-12-31 07:49:45 +0000
+++ src/roff/troff/input.cpp    2010-07-29 03:43:11 +0000
@@ -7538,6 +7538,7 @@
 #if defined(DEBUGGING)
 #define DEBUG_OPTION "D"
 #endif
+  setlocale(LC_CTYPE, "");
   while ((c = getopt_long(argc, argv,
                          "abciI:vw:W:zCEf:m:n:o:r:d:F:M:T:tqs:RU"
                          DEBUG_OPTION, long_options, 0))

Regards,
-- 
Daiki Ueno