src/archiver_hog.c
changeset 972 254427fc42ab
parent 928 0e37b8163248
child 1016 957c97389257
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/archiver_hog.c	Fri Mar 27 15:10:42 2009 -0400
@@ -0,0 +1,514 @@
+/*
+ * HOG support routines for PhysicsFS.
+ *
+ * This driver handles Descent I/II HOG archives.
+ *
+ * The format is very simple:
+ *
+ *   The file always starts with the 3-byte signature "DHF" (Descent
+ *   HOG file). After that the files of a HOG are just attached after
+ *   another, divided by a 17 bytes header, which specifies the name
+ *   and length (in bytes) of the forthcoming file! So you just read
+ *   the header with its information of how big the following file is,
+ *   and then skip exact that number of bytes to get to the next file
+ *   in that HOG.
+ *
+ *    char sig[3] = {'D', 'H', 'F'}; // "DHF"=Descent HOG File
+ *
+ *    struct {
+ *     char file_name[13]; // Filename, padded to 13 bytes with 0s
+ *     int file_size; // filesize in bytes
+ *     char data[file_size]; // The file data
+ *    } FILE_STRUCT; // Repeated until the end of the file.
+ *
+ * (That info is from http://www.descent2.com/ddn/specs/hog/)
+ *
+ * Please see the file LICENSE.txt in the source's root directory.
+ *
+ *  This file written by Bradley Bell.
+ *  Based on grp.c by Ryan C. Gordon.
+ */
+
+#if (defined PHYSFS_SUPPORTS_HOG)
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include "physfs.h"
+
+#define __PHYSICSFS_INTERNAL__
+#include "physfs_internal.h"
+
+/*
+ * One HOGentry is kept for each file in an open HOG archive.
+ */
+typedef struct
+{
+    char name[13];
+    PHYSFS_uint32 startPos;
+    PHYSFS_uint32 size;
+} HOGentry;
+
+/*
+ * One HOGinfo is kept for each open HOG archive.
+ */
+typedef struct
+{
+    char *filename;
+    PHYSFS_sint64 last_mod_time;
+    PHYSFS_uint32 entryCount;
+    HOGentry *entries;
+} HOGinfo;
+
+/*
+ * One HOGfileinfo is kept for each open file in a HOG archive.
+ */
+typedef struct
+{
+    void *handle;
+    HOGentry *entry;
+    PHYSFS_uint32 curPos;
+} HOGfileinfo;
+
+
+static void HOG_dirClose(dvoid *opaque)
+{
+    HOGinfo *info = ((HOGinfo *) opaque);
+    allocator.Free(info->filename);
+    allocator.Free(info->entries);
+    allocator.Free(info);
+} /* HOG_dirClose */
+
+
+static PHYSFS_sint64 HOG_read(fvoid *opaque, void *buffer,
+                              PHYSFS_uint32 objSize, PHYSFS_uint32 objCount)
+{
+    HOGfileinfo *finfo = (HOGfileinfo *) opaque;
+    HOGentry *entry = finfo->entry;
+    PHYSFS_uint32 bytesLeft = entry->size - finfo->curPos;
+    PHYSFS_uint32 objsLeft = (bytesLeft / objSize);
+    PHYSFS_sint64 rc;
+
+    if (objsLeft < objCount)
+        objCount = objsLeft;
+
+    rc = __PHYSFS_platformRead(finfo->handle, buffer, objSize, objCount);
+    if (rc > 0)
+        finfo->curPos += (PHYSFS_uint32) (rc * objSize);
+
+    return(rc);
+} /* HOG_read */
+
+
+static PHYSFS_sint64 HOG_write(fvoid *opaque, const void *buffer,
+                               PHYSFS_uint32 objSize, PHYSFS_uint32 objCount)
+{
+    BAIL_MACRO(ERR_NOT_SUPPORTED, -1);
+} /* HOG_write */
+
+
+static int HOG_eof(fvoid *opaque)
+{
+    HOGfileinfo *finfo = (HOGfileinfo *) opaque;
+    HOGentry *entry = finfo->entry;
+    return(finfo->curPos >= entry->size);
+} /* HOG_eof */
+
+
+static PHYSFS_sint64 HOG_tell(fvoid *opaque)
+{
+    return(((HOGfileinfo *) opaque)->curPos);
+} /* HOG_tell */
+
+
+static int HOG_seek(fvoid *opaque, PHYSFS_uint64 offset)
+{
+    HOGfileinfo *finfo = (HOGfileinfo *) opaque;
+    HOGentry *entry = finfo->entry;
+    int rc;
+
+    BAIL_IF_MACRO(offset < 0, ERR_INVALID_ARGUMENT, 0);
+    BAIL_IF_MACRO(offset >= entry->size, ERR_PAST_EOF, 0);
+    rc = __PHYSFS_platformSeek(finfo->handle, entry->startPos + offset);
+    if (rc)
+        finfo->curPos = (PHYSFS_uint32) offset;
+
+    return(rc);
+} /* HOG_seek */
+
+
+static PHYSFS_sint64 HOG_fileLength(fvoid *opaque)
+{
+    HOGfileinfo *finfo = (HOGfileinfo *) opaque;
+    return((PHYSFS_sint64) finfo->entry->size);
+} /* HOG_fileLength */
+
+
+static int HOG_fileClose(fvoid *opaque)
+{
+    HOGfileinfo *finfo = (HOGfileinfo *) opaque;
+    BAIL_IF_MACRO(!__PHYSFS_platformClose(finfo->handle), NULL, 0);
+    allocator.Free(finfo);
+    return(1);
+} /* HOG_fileClose */
+
+
+static int hog_open(const char *filename, int forWriting,
+                    void **fh, PHYSFS_uint32 *count)
+{
+    PHYSFS_uint8 buf[13];
+    PHYSFS_uint32 size;
+    PHYSFS_sint64 pos;
+
+    *count = 0;
+
+    *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, 3, 1) != 1)
+        goto openHog_failed;
+
+    if (memcmp(buf, "DHF", 3) != 0)
+    {
+        __PHYSFS_setError(ERR_UNSUPPORTED_ARCHIVE);
+        goto openHog_failed;
+    } /* if */
+
+    while (1)
+    {
+        if (__PHYSFS_platformRead(*fh, buf, 13, 1) != 1)
+            break; /* eof here is ok */
+
+        if (__PHYSFS_platformRead(*fh, &size, 4, 1) != 1)
+            goto openHog_failed;
+
+        size = PHYSFS_swapULE32(size);
+
+        (*count)++;
+
+        /* Skip over entry... */
+        pos = __PHYSFS_platformTell(*fh);
+        if (pos == -1)
+            goto openHog_failed;
+        if (!__PHYSFS_platformSeek(*fh, pos + size))
+            goto openHog_failed;
+    } /* while */
+
+    /* Rewind to start of entries... */
+    if (!__PHYSFS_platformSeek(*fh, 3))
+        goto openHog_failed;
+
+    return(1);
+
+openHog_failed:
+    if (*fh != NULL)
+        __PHYSFS_platformClose(*fh);
+
+    *count = -1;
+    *fh = NULL;
+    return(0);
+} /* hog_open */
+
+
+static int HOG_isArchive(const char *filename, int forWriting)
+{
+    void *fh;
+    PHYSFS_uint32 fileCount;
+    int retval = hog_open(filename, forWriting, &fh, &fileCount);
+
+    if (fh != NULL)
+        __PHYSFS_platformClose(fh);
+
+    return(retval);
+} /* HOG_isArchive */
+
+
+static int hog_entry_cmp(void *_a, PHYSFS_uint32 one, PHYSFS_uint32 two)
+{
+    if (one != two)
+    {
+        const HOGentry *a = (const HOGentry *) _a;
+        return(__PHYSFS_stricmpASCII(a[one].name, a[two].name));
+    } /* if */
+
+    return 0;
+} /* hog_entry_cmp */
+
+
+static void hog_entry_swap(void *_a, PHYSFS_uint32 one, PHYSFS_uint32 two)
+{
+    if (one != two)
+    {
+        HOGentry tmp;
+        HOGentry *first = &(((HOGentry *) _a)[one]);
+        HOGentry *second = &(((HOGentry *) _a)[two]);
+        memcpy(&tmp, first, sizeof (HOGentry));
+        memcpy(first, second, sizeof (HOGentry));
+        memcpy(second, &tmp, sizeof (HOGentry));
+    } /* if */
+} /* hog_entry_swap */
+
+
+static int hog_load_entries(const char *name, int forWriting, HOGinfo *info)
+{
+    void *fh = NULL;
+    PHYSFS_uint32 fileCount;
+    HOGentry *entry;
+
+    BAIL_IF_MACRO(!hog_open(name, forWriting, &fh, &fileCount), NULL, 0);
+    info->entryCount = fileCount;
+    info->entries = (HOGentry *) allocator.Malloc(sizeof(HOGentry)*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, 13, 1) != 1)
+        {
+            __PHYSFS_platformClose(fh);
+            return(0);
+        } /* if */
+
+        if (__PHYSFS_platformRead(fh, &entry->size, 4, 1) != 1)
+        {
+            __PHYSFS_platformClose(fh);
+            return(0);
+        } /* if */
+
+        entry->size = PHYSFS_swapULE32(entry->size);
+        entry->startPos = (unsigned int) __PHYSFS_platformTell(fh);
+        if (entry->startPos == -1)
+        {
+            __PHYSFS_platformClose(fh);
+            return(0);
+        }
+
+        /* Skip over entry */
+        if (!__PHYSFS_platformSeek(fh, entry->startPos + entry->size))
+        {
+            __PHYSFS_platformClose(fh);
+            return(0);
+        }
+    } /* for */
+
+    __PHYSFS_platformClose(fh);
+
+    __PHYSFS_sort(info->entries, info->entryCount,
+                  hog_entry_cmp, hog_entry_swap);
+    return(1);
+} /* hog_load_entries */
+
+
+static void *HOG_openArchive(const char *name, int forWriting)
+{
+    PHYSFS_sint64 modtime = __PHYSFS_platformGetLastModTime(name);
+    HOGinfo *info = (HOGinfo *) allocator.Malloc(sizeof (HOGinfo));
+
+    BAIL_IF_MACRO(info == NULL, ERR_OUT_OF_MEMORY, 0);
+    memset(info, '\0', sizeof (HOGinfo));
+    info->filename = (char *) allocator.Malloc(strlen(name) + 1);
+    GOTO_IF_MACRO(!info->filename, ERR_OUT_OF_MEMORY, HOG_openArchive_failed);
+
+    if (!hog_load_entries(name, forWriting, info))
+        goto HOG_openArchive_failed;
+
+    strcpy(info->filename, name);
+    info->last_mod_time = modtime;
+
+    return(info);
+
+HOG_openArchive_failed:
+    if (info != NULL)
+    {
+        if (info->filename != NULL)
+            allocator.Free(info->filename);
+        if (info->entries != NULL)
+            allocator.Free(info->entries);
+        allocator.Free(info);
+    } /* if */
+
+    return(NULL);
+} /* HOG_openArchive */
+
+
+static void HOG_enumerateFiles(dvoid *opaque, const char *dname,
+                               int omitSymLinks, PHYSFS_EnumFilesCallback cb,
+                               const char *origdir, void *callbackdata)
+{
+    /* no directories in HOG files. */
+    if (*dname == '\0')
+    {
+        HOGinfo *info = (HOGinfo *) opaque;
+        HOGentry *entry = info->entries;
+        PHYSFS_uint32 max = info->entryCount;
+        PHYSFS_uint32 i;
+
+        for (i = 0; i < max; i++, entry++)
+            cb(callbackdata, origdir, entry->name);
+    } /* if */
+} /* HOG_enumerateFiles */
+
+
+static HOGentry *hog_find_entry(HOGinfo *info, const char *name)
+{
+    char *ptr = strchr(name, '.');
+    HOGentry *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 = __PHYSFS_stricmpASCII(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);
+} /* hog_find_entry */
+
+
+static int HOG_exists(dvoid *opaque, const char *name)
+{
+    return(hog_find_entry(((HOGinfo *) opaque), name) != NULL);
+} /* HOG_exists */
+
+
+static int HOG_isDirectory(dvoid *opaque, const char *name, int *fileExists)
+{
+    *fileExists = HOG_exists(opaque, name);
+    return(0);  /* never directories in a groupfile. */
+} /* HOG_isDirectory */
+
+
+static int HOG_isSymLink(dvoid *opaque, const char *name, int *fileExists)
+{
+    *fileExists = HOG_exists(opaque, name);
+    return(0);  /* never symlinks in a groupfile. */
+} /* HOG_isSymLink */
+
+
+static PHYSFS_sint64 HOG_getLastModTime(dvoid *opaque,
+                                        const char *name,
+                                        int *fileExists)
+{
+    HOGinfo *info = ((HOGinfo *) opaque);
+    PHYSFS_sint64 retval = -1;
+
+    *fileExists = (hog_find_entry(info, name) != NULL);
+    if (*fileExists)  /* use time of HOG itself in the physical filesystem. */
+        retval = info->last_mod_time;
+
+    return(retval);
+} /* HOG_getLastModTime */
+
+
+static fvoid *HOG_openRead(dvoid *opaque, const char *fnm, int *fileExists)
+{
+    HOGinfo *info = ((HOGinfo *) opaque);
+    HOGfileinfo *finfo;
+    HOGentry *entry;
+
+    entry = hog_find_entry(info, fnm);
+    *fileExists = (entry != NULL);
+    BAIL_IF_MACRO(entry == NULL, NULL, NULL);
+
+    finfo = (HOGfileinfo *) allocator.Malloc(sizeof (HOGfileinfo));
+    BAIL_IF_MACRO(finfo == NULL, ERR_OUT_OF_MEMORY, NULL);
+
+    finfo->handle = __PHYSFS_platformOpenRead(info->filename);
+    if ( (finfo->handle == NULL) ||
+         (!__PHYSFS_platformSeek(finfo->handle, entry->startPos)) )
+    {
+        allocator.Free(finfo);
+        return(NULL);
+    } /* if */
+
+    finfo->curPos = 0;
+    finfo->entry = entry;
+    return(finfo);
+} /* HOG_openRead */
+
+
+static fvoid *HOG_openWrite(dvoid *opaque, const char *name)
+{
+    BAIL_MACRO(ERR_NOT_SUPPORTED, NULL);
+} /* HOG_openWrite */
+
+
+static fvoid *HOG_openAppend(dvoid *opaque, const char *name)
+{
+    BAIL_MACRO(ERR_NOT_SUPPORTED, NULL);
+} /* HOG_openAppend */
+
+
+static int HOG_remove(dvoid *opaque, const char *name)
+{
+    BAIL_MACRO(ERR_NOT_SUPPORTED, 0);
+} /* HOG_remove */
+
+
+static int HOG_mkdir(dvoid *opaque, const char *name)
+{
+    BAIL_MACRO(ERR_NOT_SUPPORTED, 0);
+} /* HOG_mkdir */
+
+
+const PHYSFS_ArchiveInfo __PHYSFS_ArchiveInfo_HOG =
+{
+    "HOG",
+    HOG_ARCHIVE_DESCRIPTION,
+    "Bradley Bell <btb@icculus.org>",
+    "http://icculus.org/physfs/",
+};
+
+
+const PHYSFS_Archiver __PHYSFS_Archiver_HOG =
+{
+    &__PHYSFS_ArchiveInfo_HOG,
+    HOG_isArchive,          /* isArchive() method      */
+    HOG_openArchive,        /* openArchive() method    */
+    HOG_enumerateFiles,     /* enumerateFiles() method */
+    HOG_exists,             /* exists() method         */
+    HOG_isDirectory,        /* isDirectory() method    */
+    HOG_isSymLink,          /* isSymLink() method      */
+    HOG_getLastModTime,     /* getLastModTime() method */
+    HOG_openRead,           /* openRead() method       */
+    HOG_openWrite,          /* openWrite() method      */
+    HOG_openAppend,         /* openAppend() method     */
+    HOG_remove,             /* remove() method         */
+    HOG_mkdir,              /* mkdir() method          */
+    HOG_dirClose,           /* dirClose() method       */
+    HOG_read,               /* read() method           */
+    HOG_write,              /* write() method          */
+    HOG_eof,                /* eof() method            */
+    HOG_tell,               /* tell() method           */
+    HOG_seek,               /* seek() method           */
+    HOG_fileLength,         /* fileLength() method     */
+    HOG_fileClose           /* fileClose() method      */
+};
+
+#endif  /* defined PHYSFS_SUPPORTS_HOG */
+
+/* end of hog.c ... */
+