Emit and verify machine signature (sizeof (stuff) + endianness) in cache

files. Fix bugs in FcCacheBankToIndex.
This commit is contained in:
Patrick Lam 2005-08-28 05:20:23 +00:00
parent 7f37423d8c
commit 2dbe759762
2 changed files with 84 additions and 68 deletions

View File

@ -28,6 +28,12 @@
#include <sys/utsname.h>
#include "fcint.h"
#define ENDIAN_TEST 0x12345678
#define MACHINE_SIGNATURE_SIZE 9 + 5*19 + 1
static char *
FcCacheProduceMachineSignature (void);
/*
* POSIX has broken stdio so that getc must do thread-safe locking,
* this is a serious performance problem for applications doing large
@ -1025,28 +1031,13 @@ FcCacheNextOffset(off_t w)
return ((w / PAGESIZE)+1)*PAGESIZE;
}
/* get the current arch name */
/* caller is responsible for freeing returned pointer */
static char *
FcCacheGetCurrentArch (void)
{
struct utsname b;
char * current_arch_machine_name;
if (uname(&b) == -1)
return FcFalse;
current_arch_machine_name = strdup(b.machine);
/* if (getenv ("FAKE_ARCH")) // testing purposes
current_arch_machine_name = strdup(getenv("FAKE_ARCH")); */
return current_arch_machine_name;
}
/* return the address of the segment for the provided arch,
* or -1 if arch not found */
static off_t
FcCacheSkipToArch (int fd, const char * arch)
{
char candidate_arch_machine_name[64], bytes_to_skip[7];
char candidate_arch_machine_name_count[MACHINE_SIGNATURE_SIZE + 9];
char * candidate_arch;
off_t current_arch_start = 0;
/* skip arches that are not the current arch */
@ -1055,21 +1046,20 @@ FcCacheSkipToArch (int fd, const char * arch)
long bs;
lseek (fd, current_arch_start, SEEK_SET);
if (FcCacheReadString2 (fd, candidate_arch_machine_name,
sizeof (candidate_arch_machine_name)) == 0)
break;
if (FcCacheReadString2 (fd, bytes_to_skip, 7) == 0)
break;
bs = a64l(bytes_to_skip);
if (bs == 0)
if (FcCacheReadString2 (fd, candidate_arch_machine_name_count,
sizeof (candidate_arch_machine_name_count)) == 0)
break;
if (!strlen(candidate_arch_machine_name_count))
return -1;
bs = strtol(candidate_arch_machine_name_count, &candidate_arch, 16);
candidate_arch++; /* skip leading space */
if (strcmp (candidate_arch_machine_name, arch)==0)
if (strcmp (candidate_arch, arch)==0)
break;
current_arch_start += bs;
}
if (strcmp (candidate_arch_machine_name, arch)!=0)
if (strcmp (candidate_arch, arch)!=0)
return -1;
return current_arch_start;
@ -1084,7 +1074,7 @@ static FcBool
FcCacheMoveDown (int fd, off_t start)
{
char * buf = malloc (BUF_SIZE);
char candidate_arch_machine_name[64], bytes_to_skip[7];
char candidate_arch_machine_name[MACHINE_SIGNATURE_SIZE + 9];
long bs;
int c, bytes_skipped;
@ -1095,10 +1085,10 @@ FcCacheMoveDown (int fd, off_t start)
if (FcCacheReadString2 (fd, candidate_arch_machine_name,
sizeof (candidate_arch_machine_name)) == 0)
goto done;
if (FcCacheReadString2 (fd, bytes_to_skip, 7) == 0)
if (!strlen(candidate_arch_machine_name))
goto done;
bs = a64l(bytes_to_skip);
bs = strtol(candidate_arch_machine_name, 0, 16);
if (bs == 0)
goto done;
@ -1237,11 +1227,7 @@ FcCacheReadDirs (FcConfig * config, FcGlobalCache * cache,
}
}
closedir (d);
if (FcDirCacheValid (dir))
{
FcDirCacheRead (set, dir);
}
else
if (!FcDirCacheValid (dir) || !FcDirCacheRead (set, dir))
{
if (FcDebug () & FC_DBG_FONTSET)
printf ("scan dir %s\n", dir);
@ -1293,7 +1279,7 @@ FcDirCacheRead (FcFontSet * set, const FcChar8 *dir)
FcCache metadata;
void * current_dir_block;
char * current_arch_machine_name;
char candidate_arch_machine_name[64], bytes_in_block[7];
char candidate_arch_machine_name[9+MACHINE_SIGNATURE_SIZE];
off_t current_arch_start = 0;
if (force)
@ -1301,10 +1287,10 @@ FcDirCacheRead (FcFontSet * set, const FcChar8 *dir)
if (!cache_file)
goto bail;
current_arch_machine_name = FcCacheGetCurrentArch();
current_arch_machine_name = FcCacheProduceMachineSignature();
fd = open(cache_file, O_RDONLY);
if (fd == -1)
goto bail0;
goto bail;
current_arch_start = FcCacheSkipToArch(fd, current_arch_machine_name);
if (current_arch_start < 0)
@ -1314,35 +1300,30 @@ FcDirCacheRead (FcFontSet * set, const FcChar8 *dir)
if (FcCacheReadString2 (fd, candidate_arch_machine_name,
sizeof (candidate_arch_machine_name)) == 0)
goto bail1;
if (FcCacheReadString2 (fd, bytes_in_block, 7) == 0)
goto bail1;
// sanity check for endianness issues
read(fd, &metadata, sizeof(FcCache));
if (metadata.magic != FC_CACHE_MAGIC)
goto bail1;
if (metadata.count)
{
off_t pos = FcCacheNextOffset (lseek(fd, 0, SEEK_CUR));
current_dir_block = mmap (0, metadata.count,
PROT_READ, MAP_SHARED, fd, pos);
if (current_dir_block == MAP_FAILED)
perror("");
if (!metadata.count)
goto bail1;
if (!FcFontSetUnserialize (metadata, set, current_dir_block))
goto bail1;
}
off_t pos = FcCacheNextOffset (lseek(fd, 0, SEEK_CUR));
current_dir_block = mmap (0, metadata.count,
PROT_READ, MAP_SHARED, fd, pos);
if (current_dir_block == MAP_FAILED)
perror("");
if (!FcFontSetUnserialize (metadata, set, current_dir_block))
goto bail1;
close(fd);
free (current_arch_machine_name);
free (cache_file);
return FcTrue;
bail1:
close(fd);
bail0:
free (current_arch_machine_name);
bail:
free (cache_file);
return FcFalse;
@ -1356,7 +1337,7 @@ FcDirCacheWrite (int bank, FcFontSet *set, const FcChar8 *dir)
int fd, bytes_to_write, metadata_bytes;
FcCache metadata;
off_t current_arch_start = 0, truncate_to;
char * current_arch_machine_name, bytes_written[7] = "dedbef";
char * current_arch_machine_name, * header;
void * current_dir_block, *final_dir_block;
if (!cache_file)
@ -1380,18 +1361,21 @@ FcDirCacheWrite (int bank, FcFontSet *set, const FcChar8 *dir)
if (!current_dir_block)
goto bail;
final_dir_block = FcFontSetDistributeBytes (&metadata, current_dir_block);
if ((char *)current_dir_block + bytes_to_write != final_dir_block)
goto bail;
if (!FcFontSetSerialize (bank, set))
return FcFalse;
goto bail;
if (FcDebug () & FC_DBG_CACHE)
printf ("FcDirCacheWriteDir cache_file \"%s\"\n", cache_file);
fd = open(cache_file, O_RDWR | O_CREAT, 0666);
if (fd == -1)
return FcFalse;
goto bail;
current_arch_machine_name = FcCacheGetCurrentArch();
current_arch_machine_name = FcCacheProduceMachineSignature ();
current_arch_start = FcCacheSkipToArch(fd, current_arch_machine_name);
if (current_arch_start < 0)
current_arch_start = FcCacheNextOffset (lseek(fd, 0, SEEK_END));
@ -1403,15 +1387,13 @@ FcDirCacheWrite (int bank, FcFontSet *set, const FcChar8 *dir)
if (ftruncate (fd, current_arch_start) == -1)
goto bail1;
/* reserve space for arch, count & metadata */
if (!FcCacheWriteString2 (fd, current_arch_machine_name))
goto bail1;
/* now write the address of the next offset */
truncate_to = FcCacheNextOffset(current_arch_start + bytes_to_write + metadata_bytes) -
current_arch_start;
strcpy (bytes_written, l64a(truncate_to));
if (!FcCacheWriteString2 (fd, bytes_written))
truncate_to = FcCacheNextOffset (FcCacheNextOffset (current_arch_start + metadata_bytes) + bytes_to_write) - current_arch_start;
header = malloc (10 + strlen (current_arch_machine_name));
sprintf (header, "%8x ", (int)truncate_to);
strcat (header, current_arch_machine_name);
if (!FcCacheWriteString2 (fd, header))
goto bail1;
metadata.magic = FC_CACHE_MAGIC;
@ -1419,7 +1401,7 @@ FcDirCacheWrite (int bank, FcFontSet *set, const FcChar8 *dir)
lseek (fd, FcCacheNextOffset (lseek(fd, 0, SEEK_END)), SEEK_SET);
write (fd, current_dir_block, bytes_to_write);
/* this actually serves to pad out the cache file */
/* this actually serves to pad out the cache file, if needed */
if (ftruncate (fd, current_arch_start + truncate_to) == -1)
goto bail1;
@ -1435,6 +1417,40 @@ FcDirCacheWrite (int bank, FcFontSet *set, const FcChar8 *dir)
return FcFalse;
}
static char *
FcCacheProduceMachineSignature ()
{
static char buf[MACHINE_SIGNATURE_SIZE];
int magic = ENDIAN_TEST;
char * m = (char *)&magic;
sprintf (buf, "%2x%2x%2x%2x "
"%4x %4x %4x %4x %4x %4x %4x %4x %4x %4x %4x %4x "
"%4x %4x %4x %4x %4x %4x %4x\n",
m[0], m[1], m[2], m[3],
sizeof (char),
sizeof (char *),
sizeof (int),
sizeof (FcPattern),
sizeof (FcPatternEltPtr),
sizeof (struct _FcPatternElt *),
sizeof (FcPatternElt),
sizeof (FcObjectPtr),
sizeof (FcValueListPtr),
sizeof (FcValue),
sizeof (FcValueBinding),
sizeof (struct _FcValueList *),
sizeof (FcCharSet),
sizeof (FcCharLeaf **),
sizeof (FcChar16 *),
sizeof (FcChar16),
sizeof (FcCharLeaf),
sizeof (FcChar32),
sizeof (FcCache));
return buf;
}
/* if true, ignore the cache file */
void
FcCacheForce (FcBool f)
@ -1480,9 +1496,9 @@ FcCacheBankToIndex (int bank)
if (bankId[i] == bank)
return i;
if (banks_ptr <= banks_alloc)
if (banks_ptr >= banks_alloc)
{
b = realloc (bankId, banks_alloc + 4);
b = realloc (bankId, (banks_alloc + 4) * sizeof(int));
if (!b)
return -1;

View File

@ -323,7 +323,7 @@ typedef struct _FcCaseFold {
* cache which is then rewritten to the users home directory
*/
#define FC_CACHE_MAGIC 0x12345678
#define FC_CACHE_MAGIC 0xFC20FC20
#define FC_GLOBAL_CACHE_DIR_HASH_SIZE 37
#define FC_GLOBAL_CACHE_FILE_HASH_SIZE 67