[PATCH] Support compiling without support for mmap()

[Paul Cercueil]

Some platforms don't provide functions to map memory. On these
platforms, Lightning can still be used, with user-provided code buffers.

Signed-off-by: Paul Cercueil <paul@crapouillou.net>
---
 configure.ac     |  2 +-
 lib/jit_memory.c |  1 -
 lib/lightning.c  | 20 +++++++++++++++++++-
 3 files changed, 20 insertions(+), 3 deletions(-)

diff --git a/configure.ac b/configure.ac
index 2ad0167..5b582d2 100644
--- a/configure.ac
+++ b/configure.ac
@@ -63,7 +63,7 @@ case "$target_cpu" in
     *)                                         ;;
 esac
 
-AC_CHECK_FUNCS(mremap ffsl getopt_long_only isnan isinf,,)
+AC_CHECK_FUNCS(mmap mremap ffsl getopt_long_only isnan isinf,,)
 
 AC_CHECK_HEADERS([getopt.h stdint.h],,,)
 
diff --git a/lib/jit_memory.c b/lib/jit_memory.c
index 4d7f92d..d1e3a14 100644
--- a/lib/jit_memory.c
+++ b/lib/jit_memory.c
@@ -19,7 +19,6 @@
 
 #include <lightning.h>
 #include <lightning/jit_private.h>
-#include <sys/mman.h>
 
 /*
  * Prototypes
diff --git a/lib/lightning.c b/lib/lightning.c
index 11f4069..b78bd07 100644
--- a/lib/lightning.c
+++ b/lib/lightning.c
@@ -19,7 +19,9 @@
 
 #include <lightning.h>
 #include <lightning/jit_private.h>
-#include <sys/mman.h>
+#if HAVE_MMAP
+#  include <sys/mman.h>
+#endif
 #if defined(__sgi)
 #  include <fcntl.h>
 #endif
@@ -956,10 +958,12 @@ _jit_destroy_state(jit_state_t *_jit)
 #if DEVEL_DISASSEMBLER
     jit_really_clear_state();
 #endif
+#if HAVE_MMAP
     if (!_jit->user_code)
        munmap(_jit->code.ptr, _jit->code.length);
     if (!_jit->user_data)
        munmap(_jit->data.ptr, _jit->data.length);
+#endif
     jit_free((jit_pointer_t *)&_jit);
 }
 
@@ -1895,6 +1899,9 @@ _jit_dataset(jit_state_t *_jit)
 #endif
 
     assert(!_jitc->dataset);
+#if !HAVE_MMAP
+    assert(_jit->user_data);
+#else
     if (!_jit->user_data) {
 
        /* create read only data buffer */
@@ -1912,6 +1919,7 @@ _jit_dataset(jit_state_t *_jit)
        close(mmap_fd);
 #endif
     }
+#endif /* !HAVE_MMAP */
 
     if (!_jitc->no_data)
        jit_memcpy(_jit->data.ptr, _jitc->data.ptr, _jitc->data.offset);
@@ -2026,6 +2034,9 @@ _jit_emit(jit_state_t *_jit)
 
     _jitc->emit = 1;
 
+#if !HAVE_MMAP
+    assert(_jit->user_code);
+#else
     if (!_jit->user_code) {
 #if defined(__sgi)
        mmap_fd = open("/dev/zero", O_RDWR);
@@ -2035,6 +2046,7 @@ _jit_emit(jit_state_t *_jit)
                              MAP_PRIVATE | MAP_ANON, mmap_fd, 0);
        assert(_jit->code.ptr != MAP_FAILED);
     }
+#endif /* !HAVE_MMAP */
     _jitc->code.end = _jit->code.ptr + _jit->code.length -
        jit_get_max_instr();
     _jit->pc.uc = _jit->code.ptr;
@@ -2048,6 +2060,9 @@ _jit_emit(jit_state_t *_jit)
                     node->code == jit_code_epilog))
                    node->flag &= ~jit_flag_patch;
            }
+#if !HAVE_MMAP
+           assert(_jit->user_code);
+#else
            if (_jit->user_code)
                goto fail;
 #if GET_JIT_SIZE
@@ -2081,6 +2096,7 @@ _jit_emit(jit_state_t *_jit)
            _jitc->code.end = _jit->code.ptr + _jit->code.length -
                jit_get_max_instr();
            _jit->pc.uc = _jit->code.ptr;
+#endif /* !HAVE_MMAP */
        }
        else
            break;
@@ -2097,6 +2113,7 @@ _jit_emit(jit_state_t *_jit)
 
     if (_jit->user_data)
        jit_free((jit_pointer_t *)&_jitc->data.ptr);
+#if HAVE_MMAP
     else {
        result = mprotect(_jit->data.ptr, _jit->data.length, PROT_READ);
        assert(result == 0);
@@ -2106,6 +2123,7 @@ _jit_emit(jit_state_t *_jit)
                          PROT_READ | PROT_EXEC);
        assert(result == 0);
     }
+#endif /* HAVE_MMAP */
 
     return (_jit->code.ptr);
 fail:
-- 
2.35.1