/*

* 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 ...)

*

* As it was never a concern in the DOS-based Duke Nukem days, I treat these

* archives as CASE-INSENSITIVE. Opening "myfile.txt" and "MYFILE.TXT" both

* work, and get the same file.

*

* Please see the file LICENSE in the source's root directory.

*

* This file written by Ryan C. Gordon.

*/

#include <stdio.h>

#include <stdlib.h>

#include <string.h>

#include <errno.h>

#include <sys/stat.h>

#include <sys/types.h>

#include <fcntl.h>

#include <unistd.h>

#include <assert.h>

#include "physfs.h"

#define __PHYSICSFS_INTERNAL__

#include "physfs_internal.h"

#if (!defined PHYSFS_SUPPORTS_GRP)

#error PHYSFS_SUPPORTS_GRP must be defined.

#endif

typedef struct

{

FILE *handle;

int totalEntries;

} GRPinfo;

typedef struct

{

int startPos;

int curPos;

int size;

} GRPfileinfo;

extern const DirFunctions __PHYSFS_DirFunctions_GRP;

static const FileFunctions __PHYSFS_FileFunctions_GRP;

static int GRP_read(FileHandle *handle, void *buffer,

unsigned int objSize, unsigned int objCount)

{

GRPfileinfo *finfo = (GRPfileinfo *) (handle->opaque);

FILE *fh = (FILE *) (((GRPinfo *) (handle->dirHandle->opaque))->handle);

int bytesLeft = (finfo->startPos + finfo->size) - finfo->curPos;

int objsLeft = bytesLeft / objSize;

int retval = 0;

if (objsLeft < objCount)

objCount = objsLeft;

errno = 0;

BAIL_IF_MACRO(fseek(fh,finfo->curPos,SEEK_SET) == -1,strerror(errno),-1);

errno = 0;

retval = fread(buffer, objSize, objCount, fh);

BAIL_IF_MACRO((retval < objCount) && (ferror(fh)),strerror(errno),retval);

return(retval);

} /* GRP_read */

static int GRP_eof(FileHandle *handle)

{

GRPfileinfo *finfo = (GRPfileinfo *) (handle->opaque);

return(finfo->curPos >= finfo->startPos + finfo->size);

} /* GRP_eof */

static int GRP_tell(FileHandle *handle)

{

GRPfileinfo *finfo = (GRPfileinfo *) (handle->opaque);

return(finfo->curPos - finfo->startPos);

} /* GRP_tell */

static int GRP_seek(FileHandle *handle, int offset)

{

GRPfileinfo *finfo = (GRPfileinfo *) (handle->opaque);

BAIL_IF_MACRO(offset < 0, ERR_INVALID_ARGUMENT, 0);

BAIL_IF_MACRO(newPos > finfo->startPos + finfo->size, ERR_PAST_EOF, 0);

finfo->curPos = newPos;

return(1);

} /* GRP_seek */

static int GRP_fileLength(FileHandle *handle)

{

GRPfileinfo *finfo = (GRPfileinfo *) (handle->opaque);

return(finfo->size);

} /* GRP_fileLength */

static int GRP_fileClose(FileHandle *handle)

{

free(handle->opaque);

free(handle);

return(1);

} /* GRP_fileClose */

static int openGrp(const char *filename, int forWriting, FILE **fh, int *count)

{

char buf[12];

assert(sizeof (int) == 4);

*fh = NULL;

BAIL_IF_MACRO(forWriting, ERR_ARC_IS_READ_ONLY, 0);

errno = 0;

*fh = fopen(filename, "rb");

BAIL_IF_MACRO(*fh == NULL, strerror(errno), 0);

errno = 0;

BAIL_IF_MACRO(fread(buf, 12, 1, *fh) != 1, strerror(errno), 0);

BAIL_IF_MACRO(strncmp(buf, "KenSilverman", 12) != 0,

ERR_UNSUPPORTED_ARCHIVE, 0);

if (fread(count, 4, 1, *fh) != 1)

*count = 0;

return(1);

} /* openGrp */

static int GRP_isArchive(const char *filename, int forWriting)

{

FILE *fh;

int fileCount;

int retval = openGrp(filename, forWriting, &fh, &fileCount);

if (fh != NULL)

fclose(fh);

return(retval);

} /* GRP_isArchive */

static DirHandle *GRP_openArchive(const char *name, int forWriting)

{

FILE *fh;

int fileCount;

DirHandle *retval = malloc(sizeof (DirHandle));

BAIL_IF_MACRO(retval == NULL, ERR_OUT_OF_MEMORY, NULL);

retval->opaque = malloc(sizeof (GRPinfo));

if (retval->opaque == NULL)

{

free(retval);

BAIL_IF_MACRO(1, ERR_OUT_OF_MEMORY, NULL);

} /* if */

if (!openGrp(name, forWriting, &fh, &fileCount))

{

if (fh != NULL)

fclose(fh);

free(retval->opaque);

free(retval);

} /* if */

((GRPinfo *) retval->opaque)->handle = fh;

((GRPinfo *) retval->opaque)->totalEntries = fileCount;

retval->funcs = &__PHYSFS_DirFunctions_GRP;

return(retval);

} /* GRP_openArchive */

static LinkedStringList *GRP_enumerateFiles(DirHandle *h,

const char *dirname,

int omitSymLinks)

{

char buf[16];

GRPinfo *g = (GRPinfo *) (h->opaque);

FILE *fh = g->handle;

int i;

LinkedStringList *retval = NULL;

LinkedStringList *l = NULL;

LinkedStringList *prev = NULL;

if (*dirname != '\0') /* no directories in GRP files. */

return(NULL);

/* jump to first file entry... */

errno = 0;

BAIL_IF_MACRO(fseek(fh, 16, SEEK_SET) == -1, strerror(errno), NULL);

for (i = 0; i < g->totalEntries; i++)

{

errno = 0;

BAIL_IF_MACRO(fread(buf, 16, 1, fh) != 1, strerror(errno), retval);

buf[12] = '\0'; /* FILENAME.EXT is all you get. */

l = (LinkedStringList *) malloc(sizeof (LinkedStringList));

break;

l->str = (char *) malloc(strlen(buf) + 1);

if (l->str == NULL)

{

free(l);

break;

} /* if */

strcpy(l->str, buf);

if (retval == NULL)

retval = l;

else

prev->next = l;

prev = l;

l->next = NULL;

} /* for */

return(retval);

} /* GRP_enumerateFiles */

static int getFileEntry(DirHandle *h, const char *name, int *size)

{

char buf[16];

GRPinfo *g = (GRPinfo *) (h->opaque);

FILE *fh = g->handle;

int i;

char *ptr;

/* Rule out filenames to avoid unneeded file i/o... */

if (strchr(name, '/') != NULL) /* no directories in groupfiles. */

return(-1);

ptr = strchr(name, '.');

if ((ptr) && (strlen(ptr) > 4)) /* 3 char extension at most. */

return(-1);

if (strlen(name) > 12)

return(-1);

/* jump to first file entry... */

errno = 0;

BAIL_IF_MACRO(fseek(fh, 16, SEEK_SET) == -1, strerror(errno), -1);

for (i = 0; i < g->totalEntries; i++)

{

int fsize;

errno = 0;

BAIL_IF_MACRO(fread(buf, 16, 1, fh) != 1, strerror(errno), -1);

fsize = *((int *) (buf + 12));

buf[12] = '\0'; /* FILENAME.EXT is all you get. */

if (__PHYSFS_platformStricmp(buf, name) == 0)

{

if (size != NULL)

*size = fsize;

return(retval);

} /* if */

retval += fsize;

} /* for */

return(-1); /* not found. */

} /* getFileEntry */

static int GRP_exists(DirHandle *h, const char *name)

{

return(getFileEntry(h, name, NULL) != -1);

} /* 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 FileHandle *GRP_openRead(DirHandle *h, const char *name)

{

FileHandle *retval;

GRPfileinfo *finfo;

int size, offset;

offset = getFileEntry(h, name, &size);

BAIL_IF_MACRO(offset == -1, ERR_NO_SUCH_FILE, 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_IF_MACRO(1, ERR_OUT_OF_MEMORY, NULL);

} /* if */

finfo->startPos = offset;

finfo->curPos = offset;

finfo->size = size;

retval->opaque = (void *) finfo;

retval->funcs = &__PHYSFS_FileFunctions_GRP;

retval->dirHandle = h;

return(retval);

} /* GRP_openRead */

static void GRP_dirClose(DirHandle *h)

{

fclose( ((GRPinfo *) h->opaque)->handle );

free(h->opaque);

free(h);

} /* GRP_dirClose */

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_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",

"Ryan C. Gordon (icculus@linuxgames.com)",

"http://www.icculus.org/~icculus/",

};

/* end of grp.c ... */