mpq-file almost done.

1 files changed, 143 insertions, 1 deletions

diff --git a/mpq-file.c b/mpq-file.c
index 2fc372b..9cc7788 100644
--- a/mpq-file.c
+++ b/mpq-file.c
@@ -1,12 +1,154 @@
+#include <stdlib.h>
+#include <memory.h>
 #include "mpq-bios.h"
 #include "mpq-file.h"
+#include "mpq-errors.h"
+#include "int-bios.h"
+#include "errors.h"
 
 struct mpq_file_t {
     struct mpq_archive_t * mpq_a;
     int entry;
     int number_of_sectors;
     int remaining_bytes;
-    char * buffer;
     int current_sector;
     uint32_t cursor;
+    uint64_t offset;
+    uint32_t file_size;
+    uint32_t sector_size;
+
+    char * buffer;
+    uint64_t * offsets;
 };
+
+struct mpq_file_t * mpqlib_open_file(struct mpq_archive_t * mpq_a, int entry) {
+    struct mpq_file_t * r;
+    int i;
+    
+    if (mpqlib_ioctl(mpq_a, MPQLIB_IOCTL_ENTRY_EXISTS, entry)) {
+	return NULL;
+    }
+    
+    if (!(r = (struct mpq_file_t *) malloc(sizeof(struct mpq_file_t)))) {
+	__mpqlib_errno = MPQLIB_ERROR_MEMORY;
+	return NULL;
+    }
+    
+    r->sector_size = mpqlib_ioctl(mpq_a, MPQLIB_IOCTL_GET_SECTOR_SIZE, 0);
+    
+    if (!(r->buffer = malloc(r->sector_size))) {
+	free(r);
+	__mpqlib_errno = MPQLIB_ERROR_MEMORY;
+	return NULL;
+    }
+    
+    r->entry = entry;
+    r->file_size = mpqlib_ioctl(mpq_a, MPQLIB_IOCTL_GET_FILE_SIZE, entry);
+    r->offset = mpqlib_ioctl(mpq_a, MPQLIB_IOCTL_GET_BLOCK_OFFSET, entry);
+    r->number_of_sectors = r->file_size / r->sector_size;
+    if ((r->remaining_bytes = (r->file_size % r->sector_size))) {
+	r->number_of_sectors++;
+    }
+    r->current_sector = -1;
+    r->cursor = 0;
+    
+    if (!(r->offsets = (uint64_t *) malloc(r->number_of_sectors * sizeof(uint64_t)))) {
+	free(r->buffer);
+	free(r);
+	__mpqlib_errno = MPQLIB_ERROR_MEMORY;
+	return NULL;
+    }
+    
+    __mpqlib_seek(mpq_a, r->offset);
+    for (i = 0; i < r->number_of_sectors; i++) {
+	uint32_t o;
+	__mpqlib_read(mpq_a, &o, 4);
+	r->offsets[i] = r->offset + o;
+    }
+    
+    return r;
+}
+
+struct mpq_file_t * mpqlib_open_filename(struct mpq_archive_t * mpq_a, const char * fname) {
+    int e;
+    
+    if ((e = mpqlib_find_hash_entry_by_name(mpq_a, fname, 0, 0)) < 0)
+	return NULL;
+
+    return mpqlib_open_file(mpq_a, e);
+}
+
+void mpqlib_close_file(struct mpq_file_t * mpq_f) {
+    free(mpq_f->buffer);
+    free(mpq_f->offsets);
+    free(mpq_f);
+}
+
+static void cache_sector(struct mpq_file_t * mpq_f, int sector) {
+    if (mpq_f->current_sector != sector) {
+        __mpqlib_seek(mpq_f->mpq_a, mpq_f->offsets[sector]);
+	__mpqlib_read(mpq_f->mpq_a, mpq_f->buffer, mpq_f->sector_size);
+	mpq_f->current_sector = sector;
+    }
+}
+
+uint32_t mpqlib_read(struct mpq_file_t * mpq_f, void * buffer, uint32_t size) {
+    int sector_begin, sector_end;
+    uint32_t offset_begin, offset_end;
+    
+    uint32_t first_sector_begins, last_sector_ends;
+    
+    if ((size + mpq_f->cursor) >= mpq_f->file_size)
+	size = mpq_f->file_size - mpq_f->cursor;
+
+    offset_begin = mpq_f->cursor;
+    sector_begin = offset_begin / mpq_f->sector_size;
+    first_sector_begins = offset_begin % mpq_f->sector_size;
+    
+    offset_end = size + mpq_f->cursor;
+    sector_end = offset_end / mpq_f->sector_size;
+    last_sector_ends = offset_end % mpq_f->sector_size;
+    
+    if (!(offset_end % mpq_f->sector_size)) {
+	sector_end--;
+	last_sector_ends = mpq_f->sector_size;
+    }
+    
+    if (sector_begin == sector_end) {
+	cache_sector(mpq_f, sector_begin);
+	memcpy(buffer, mpq_f->buffer + first_sector_begins, size);
+	return size;
+    }
+
+    /* ... */
+
+    return size;
+}
+
+uint32_t mpqlib_seek(struct mpq_file_t * mpq_f, int32_t offset, enum mpqlib_file_seek_t wheel) {
+    switch (wheel) {
+    case MPQLIB_SEEK_SET:
+	if (offset < 0)
+	    offset = 0;
+	mpq_f->cursor = offset;
+	break;
+    case MPQLIB_SEEK_CUR:
+	if ((-offset) >= mpq_f->cursor)
+	    offset = -mpq_f->cursor;
+	mpq_f->cursor += offset;
+	break;
+    case MPQLIB_SEEK_END:
+	if (offset > 0)
+	    offset = 0;
+	if ((-offset) >= mpq_f->file_size)
+	    offset = -mpq_f->file_size;
+	mpq_f->cursor += offset;
+	break;
+    default:
+	__mpqlib_errno = MPQLIB_ERROR_UNKNOWN;
+	return 0xffffffff;
+    }
+    if (mpq_f->cursor >= mpq_f->file_size)
+	mpq_f->cursor = mpq_f->file_size;
+    return mpq_f->cursor;
+}