physfs/archivers/grp.c

547 lines
15 KiB
C

/*
* GRP support routines for PhysicsFS.
*
* This driver handles BUILD engine archives ("groupfiles"). This format
* (but not this driver) was put together by Ken Silverman.
*
* The format is simple enough. In Ken's words:
*
* What's the .GRP file format?
*
* The ".grp" file format is just a collection of a lot of files stored
* into 1 big one. I tried to make the format as simple as possible: The
* first 12 bytes contains my name, "KenSilverman". The next 4 bytes is
* the number of files that were compacted into the group file. Then for
* each file, there is a 16 byte structure, where the first 12 bytes are
* the filename, and the last 4 bytes are the file's size. The rest of
* the group file is just the raw data packed one after the other in the
* same order as the list of files.
*
* (That info is from http://www.advsys.net/ken/build.htm ...)
*
* Please see the file LICENSE in the source's root directory.
*
* This file written by Ryan C. Gordon.
*/
#if HAVE_CONFIG_H
# include <config.h>
#endif
#if (defined PHYSFS_SUPPORTS_GRP)
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <errno.h>
#include <fcntl.h>
#include <assert.h>
#include "physfs.h"
#define __PHYSICSFS_INTERNAL__
#include "physfs_internal.h"
/*
* When sorting the grp entries in an archive, we use a modified QuickSort.
* When there are less then GRP_QUICKSORT_THRESHOLD entries left to sort,
* we switch over to an InsertionSort for the remainder. Tweak to taste.
*/
#define GRP_QUICKSORT_THRESHOLD 4
typedef struct
{
char name[13];
PHYSFS_uint64 startPos;
PHYSFS_uint64 size;
} GRPentry;
typedef struct
{
char *filename;
PHYSFS_sint64 last_mod_time;
PHYSFS_uint32 entryCount;
GRPentry *entries;
} GRPinfo;
typedef struct
{
void *handle;
GRPentry *entry;
PHYSFS_sint64 curPos;
} GRPfileinfo;
static void GRP_dirClose(DirHandle *h);
static PHYSFS_sint64 GRP_read(FileHandle *handle, void *buffer,
PHYSFS_uint32 objSize, PHYSFS_uint32 objCount);
static int GRP_eof(FileHandle *handle);
static PHYSFS_sint64 GRP_tell(FileHandle *handle);
static int GRP_seek(FileHandle *handle, PHYSFS_uint64 offset);
static PHYSFS_sint64 GRP_fileLength(FileHandle *handle);
static int GRP_fileClose(FileHandle *handle);
static int GRP_isArchive(const char *filename, int forWriting);
static DirHandle *GRP_openArchive(const char *name, int forWriting);
static LinkedStringList *GRP_enumerateFiles(DirHandle *h,
const char *dirname,
int omitSymLinks);
static int GRP_exists(DirHandle *h, const char *name);
static int GRP_isDirectory(DirHandle *h, const char *name);
static int GRP_isSymLink(DirHandle *h, const char *name);
static PHYSFS_sint64 GRP_getLastModTime(DirHandle *h, const char *name);
static FileHandle *GRP_openRead(DirHandle *h, const char *name);
static const FileFunctions __PHYSFS_FileFunctions_GRP =
{
GRP_read, /* read() method */
NULL, /* write() method */
GRP_eof, /* eof() method */
GRP_tell, /* tell() method */
GRP_seek, /* seek() method */
GRP_fileLength, /* fileLength() method */
GRP_fileClose /* fileClose() method */
};
const DirFunctions __PHYSFS_DirFunctions_GRP =
{
GRP_isArchive, /* isArchive() method */
GRP_openArchive, /* openArchive() method */
GRP_enumerateFiles, /* enumerateFiles() method */
GRP_exists, /* exists() method */
GRP_isDirectory, /* isDirectory() method */
GRP_isSymLink, /* isSymLink() method */
GRP_getLastModTime, /* getLastModTime() method */
GRP_openRead, /* openRead() method */
NULL, /* openWrite() method */
NULL, /* openAppend() method */
NULL, /* remove() method */
NULL, /* mkdir() method */
GRP_dirClose /* dirClose() method */
};
const PHYSFS_ArchiveInfo __PHYSFS_ArchiveInfo_GRP =
{
"GRP",
"Build engine Groupfile format",
"Ryan C. Gordon <icculus@clutteredmind.org>",
"http://www.icculus.org/physfs/",
};
static void GRP_dirClose(DirHandle *h)
{
GRPinfo *info = ((GRPinfo *) h->opaque);
free(info->filename);
free(info->entries);
free(info);
free(h);
} /* GRP_dirClose */
static PHYSFS_sint64 GRP_read(FileHandle *handle, void *buffer,
PHYSFS_uint32 objSize, PHYSFS_uint32 objCount)
{
GRPfileinfo *finfo = (GRPfileinfo *) (handle->opaque);
GRPentry *entry = finfo->entry;
PHYSFS_uint64 bytesLeft = entry->size - finfo->curPos;
PHYSFS_uint64 objsLeft = (bytesLeft / objSize);
PHYSFS_sint64 rc;
if (objsLeft < objCount)
objCount = (PHYSFS_uint32) objsLeft;
rc = __PHYSFS_platformRead(finfo->handle, buffer, objSize, objCount);
if (rc > 0)
finfo->curPos += (rc * objSize);
return(rc);
} /* GRP_read */
static int GRP_eof(FileHandle *handle)
{
GRPfileinfo *finfo = (GRPfileinfo *) (handle->opaque);
GRPentry *entry = finfo->entry;
return(finfo->curPos >= (PHYSFS_sint64) entry->size);
} /* GRP_eof */
static PHYSFS_sint64 GRP_tell(FileHandle *handle)
{
return(((GRPfileinfo *) (handle->opaque))->curPos);
} /* GRP_tell */
static int GRP_seek(FileHandle *handle, PHYSFS_uint64 offset)
{
GRPfileinfo *finfo = (GRPfileinfo *) (handle->opaque);
GRPentry *entry = finfo->entry;
PHYSFS_uint64 newPos = (entry->startPos + offset);
int rc;
BAIL_IF_MACRO(offset < 0, ERR_INVALID_ARGUMENT, 0);
BAIL_IF_MACRO(newPos > entry->startPos + entry->size, ERR_PAST_EOF, 0);
rc = __PHYSFS_platformSeek(finfo->handle, newPos);
if (rc)
finfo->curPos = offset;
return(rc);
} /* GRP_seek */
static PHYSFS_sint64 GRP_fileLength(FileHandle *handle)
{
return(((GRPfileinfo *) handle->opaque)->entry->size);
} /* GRP_fileLength */
static int GRP_fileClose(FileHandle *handle)
{
GRPfileinfo *finfo = ((GRPfileinfo *) handle->opaque);
BAIL_IF_MACRO(!__PHYSFS_platformClose(finfo->handle), NULL, 0);
free(finfo);
free(handle);
return(1);
} /* GRP_fileClose */
static int grp_open(const char *filename, int forWriting,
void **fh, PHYSFS_uint32 *count)
{
PHYSFS_uint8 buf[12];
*fh = NULL;
BAIL_IF_MACRO(forWriting, ERR_ARC_IS_READ_ONLY, 0);
*fh = __PHYSFS_platformOpenRead(filename);
BAIL_IF_MACRO(*fh == NULL, NULL, 0);
if (__PHYSFS_platformRead(*fh, buf, 12, 1) != 1)
goto openGrp_failed;
if (memcmp(buf, "KenSilverman", 12) != 0)
{
__PHYSFS_setError(ERR_UNSUPPORTED_ARCHIVE);
goto openGrp_failed;
} /* if */
if (__PHYSFS_platformRead(*fh, count, sizeof (PHYSFS_uint32), 1) != 1)
goto openGrp_failed;
*count = PHYSFS_swapULE32(*count);
return(1);
openGrp_failed:
if (*fh != NULL)
__PHYSFS_platformClose(*fh);
*count = -1;
*fh = NULL;
return(0);
} /* grp_open */
static int GRP_isArchive(const char *filename, int forWriting)
{
void *fh;
PHYSFS_uint32 fileCount;
int retval = grp_open(filename, forWriting, &fh, &fileCount);
if (fh != NULL)
__PHYSFS_platformClose(fh);
return(retval);
} /* GRP_isArchive */
static void grp_entry_swap(GRPentry *a, PHYSFS_uint32 one, PHYSFS_uint32 two)
{
GRPentry tmp;
memcpy(&tmp, &a[one], sizeof (GRPentry));
memcpy(&a[one], &a[two], sizeof (GRPentry));
memcpy(&a[two], &tmp, sizeof (GRPentry));
} /* grp_entry_swap */
static void grp_quick_sort(GRPentry *a, PHYSFS_uint32 lo, PHYSFS_uint32 hi)
{
PHYSFS_uint32 i;
PHYSFS_uint32 j;
GRPentry *v;
if ((hi - lo) > GRP_QUICKSORT_THRESHOLD)
{
i = (hi + lo) / 2;
if (strcmp(a[lo].name, a[i].name) > 0) grp_entry_swap(a, lo, i);
if (strcmp(a[lo].name, a[hi].name) > 0) grp_entry_swap(a, lo, hi);
if (strcmp(a[i].name, a[hi].name) > 0) grp_entry_swap(a, i, hi);
j = hi - 1;
grp_entry_swap(a, i, j);
i = lo;
v = &a[j];
while (1)
{
while(strcmp(a[++i].name, v->name) < 0) {}
while(strcmp(a[--j].name, v->name) > 0) {}
if (j < i)
break;
grp_entry_swap(a, i, j);
} /* while */
grp_entry_swap(a, i, hi-1);
grp_quick_sort(a, lo, j);
grp_quick_sort(a, i+1, hi);
} /* if */
} /* grp_quick_sort */
static void grp_insertion_sort(GRPentry *a, PHYSFS_uint32 lo, PHYSFS_uint32 hi)
{
PHYSFS_uint32 i;
PHYSFS_uint32 j;
GRPentry tmp;
for (i = lo + 1; i <= hi; i++)
{
memcpy(&tmp, &a[i], sizeof (GRPentry));
j = i;
while ((j > lo) && (strcmp(a[j - 1].name, tmp.name) > 0))
{
memcpy(&a[j], &a[j - 1], sizeof (GRPentry));
j--;
} /* while */
memcpy(&a[j], &tmp, sizeof (GRPentry));
} /* for */
} /* grp_insertion_sort */
static void grp_sort_entries(GRPentry *entries, PHYSFS_uint32 max)
{
/*
* Fast Quicksort algorithm inspired by code from here:
* http://www.cs.ubc.ca/spider/harrison/Java/sorting-demo.html
*/
if (max <= GRP_QUICKSORT_THRESHOLD)
grp_quick_sort(entries, 0, max - 1);
grp_insertion_sort(entries, 0, max - 1);
} /* grp_sort_entries */
static int grp_load_entries(const char *name, int forWriting, GRPinfo *info)
{
void *fh = NULL;
PHYSFS_uint32 fileCount;
PHYSFS_uint32 location = 32; /* sizeof sig + sizeof 1st file header. */
GRPentry *entry;
char *ptr;
BAIL_IF_MACRO(!grp_open(name, forWriting, &fh, &fileCount), NULL, 0);
info->entryCount = fileCount;
info->entries = (GRPentry *) malloc(sizeof (GRPentry) * fileCount);
if (info->entries == NULL)
{
__PHYSFS_platformClose(fh);
BAIL_MACRO(ERR_OUT_OF_MEMORY, 0);
} /* if */
for (entry = info->entries; fileCount > 0; fileCount--, entry++)
{
if (__PHYSFS_platformRead(fh, &entry->name, 12, 1) != 1)
{
__PHYSFS_platformClose(fh);
return(0);
} /* if */
entry->name[12] = '\0'; /* name isn't null-terminated in file. */
if ((ptr = strchr(entry->name, ' ')) != NULL)
*ptr = '\0'; /* trim extra spaces. */
if (__PHYSFS_platformRead(fh, &entry->size, 4, 1) != 1)
{
__PHYSFS_platformClose(fh);
return(0);
} /* if */
entry->size = PHYSFS_swapULE32(entry->size);
entry->startPos = location;
location += entry->size + 16;
} /* for */
__PHYSFS_platformClose(fh);
grp_sort_entries(info->entries, info->entryCount);
return(1);
} /* grp_load_entries */
static DirHandle *GRP_openArchive(const char *name, int forWriting)
{
GRPinfo *info;
DirHandle *retval = malloc(sizeof (DirHandle));
PHYSFS_sint64 modtime = __PHYSFS_platformGetLastModTime(name);
BAIL_IF_MACRO(retval == NULL, ERR_OUT_OF_MEMORY, NULL);
info = retval->opaque = malloc(sizeof (GRPinfo));
if (info == NULL)
{
__PHYSFS_setError(ERR_OUT_OF_MEMORY);
goto GRP_openArchive_failed;
} /* if */
memset(info, '\0', sizeof (GRPinfo));
info->filename = (char *) malloc(strlen(name) + 1);
if (info->filename == NULL)
{
__PHYSFS_setError(ERR_OUT_OF_MEMORY);
goto GRP_openArchive_failed;
} /* if */
if (!grp_load_entries(name, forWriting, info))
goto GRP_openArchive_failed;
strcpy(info->filename, name);
info->last_mod_time = modtime;
retval->funcs = &__PHYSFS_DirFunctions_GRP;
return(retval);
GRP_openArchive_failed:
if (retval != NULL)
{
if (retval->opaque != NULL)
{
if (info->filename != NULL)
free(info->filename);
if (info->entries != NULL)
free(info->entries);
free(info);
} /* if */
free(retval);
} /* if */
return(NULL);
} /* GRP_openArchive */
static LinkedStringList *GRP_enumerateFiles(DirHandle *h,
const char *dirname,
int omitSymLinks)
{
GRPinfo *info = ((GRPinfo *) h->opaque);
GRPentry *entry = info->entries;
LinkedStringList *retval = NULL, *p = NULL;
PHYSFS_uint32 max = info->entryCount;
PHYSFS_uint32 i;
/* no directories in GRP files. */
BAIL_IF_MACRO(*dirname != '\0', ERR_NOT_A_DIR, NULL);
for (i = 0; i < max; i++, entry++)
retval = __PHYSFS_addToLinkedStringList(retval, &p, entry->name, -1);
return(retval);
} /* GRP_enumerateFiles */
static GRPentry *grp_find_entry(GRPinfo *info, const char *name)
{
char *ptr = strchr(name, '.');
GRPentry *a = info->entries;
PHYSFS_sint32 lo = 0;
PHYSFS_sint32 hi = (PHYSFS_sint32) (info->entryCount - 1);
PHYSFS_sint32 middle;
int rc;
/*
* Rule out filenames to avoid unneeded processing...no dirs,
* big filenames, or extensions > 3 chars.
*/
BAIL_IF_MACRO((ptr) && (strlen(ptr) > 4), ERR_NO_SUCH_FILE, NULL);
BAIL_IF_MACRO(strlen(name) > 12, ERR_NO_SUCH_FILE, NULL);
BAIL_IF_MACRO(strchr(name, '/') != NULL, ERR_NO_SUCH_FILE, NULL);
while (lo <= hi)
{
middle = lo + ((hi - lo) / 2);
rc = strcmp(name, a[middle].name);
if (rc == 0) /* found it! */
return(&a[middle]);
else if (rc > 0)
lo = middle + 1;
else
hi = middle - 1;
} /* while */
BAIL_MACRO(ERR_NO_SUCH_FILE, NULL);
} /* grp_find_entry */
static int GRP_exists(DirHandle *h, const char *name)
{
return(grp_find_entry(((GRPinfo *) h->opaque), name) != NULL);
} /* GRP_exists */
static int GRP_isDirectory(DirHandle *h, const char *name)
{
return(0); /* never directories in a groupfile. */
} /* GRP_isDirectory */
static int GRP_isSymLink(DirHandle *h, const char *name)
{
return(0); /* never symlinks in a groupfile. */
} /* GRP_isSymLink */
static PHYSFS_sint64 GRP_getLastModTime(DirHandle *h, const char *name)
{
/* Just return the time of the GRP itself in the physical filesystem. */
return(((GRPinfo *) h->opaque)->last_mod_time);
} /* GRP_getLastModTime */
static FileHandle *GRP_openRead(DirHandle *h, const char *name)
{
GRPinfo *info = ((GRPinfo *) h->opaque);
FileHandle *retval;
GRPfileinfo *finfo;
GRPentry *entry;
entry = grp_find_entry(info, name);
BAIL_IF_MACRO(entry == NULL, NULL, NULL);
retval = (FileHandle *) malloc(sizeof (FileHandle));
BAIL_IF_MACRO(retval == NULL, ERR_OUT_OF_MEMORY, NULL);
finfo = (GRPfileinfo *) malloc(sizeof (GRPfileinfo));
if (finfo == NULL)
{
free(retval);
BAIL_MACRO(ERR_OUT_OF_MEMORY, NULL);
} /* if */
finfo->handle = __PHYSFS_platformOpenRead(info->filename);
if ( (finfo->handle == NULL) ||
(!__PHYSFS_platformSeek(finfo->handle, entry->startPos)) )
{
free(finfo);
free(retval);
return(NULL);
} /* if */
finfo->curPos = 0;
finfo->entry = entry;
retval->opaque = (void *) finfo;
retval->funcs = &__PHYSFS_FileFunctions_GRP;
retval->dirHandle = h;
return(retval);
} /* GRP_openRead */
#endif /* defined PHYSFS_SUPPORTS_GRP */
/* end of grp.c ... */