AmendHub

--- bile.c Wed Jan 5 20:45:19 2022 +++ bile.c Thu Jan 6 17:07:39 2022 @@ -22,8 +22,8 @@ static short _bile_error; short bile_write_map(struct bile *bile); void bile_sort_by_pos(struct bile *bile); -size_t bile_xwriteat(struct bile *bile, const size_t pos, const size_t len, - const void *data); +size_t bile_xwriteat(struct bile *bile, const size_t pos, const void *data, + const size_t len); short bile_error(void) @@ -52,6 +52,7 @@ bile_create(const Str255 filename, const OSType creato bile = xmalloczero(sizeof(struct bile)); bile->vrefid = fh; + bile->map_ptr.type = BILE_TYPE_MAPPTR; memcpy(bile->filename, filename, sizeof(bile->filename)); /* write magic */ @@ -62,16 +63,11 @@ bile_create(const Str255 filename, const OSType creato if (_bile_error) goto create_bail; - /* write empty map */ - len = sizeof(long); - _bile_error = FSWrite(bile->vrefid, &len, &bile->map_pos); + /* write header pointing to blank map */ + len = sizeof(bile->map_ptr); + _bile_error = FSWrite(bile->vrefid, &len, &bile->map_ptr); if (_bile_error) goto create_bail; - - len = sizeof(long); - _bile_error = FSWrite(bile->vrefid, &len, &bile->map_size); - if (_bile_error) - goto create_bail; GetFPos(fh, &bile->file_size); @@ -92,6 +88,7 @@ struct bile * bile_open(const Str255 filename) { struct bile *bile = NULL; + struct bile_object map_obj; size_t file_size, map_size, size; short fh; char magic[BILE_MAGIC_LEN + 1]; @@ -125,34 +122,44 @@ bile_open(const Str255 filename) memcpy(bile->filename, filename, sizeof(filename)); bile->file_size = file_size; - /* load map */ - size = sizeof(long); - _bile_error = FSRead(bile->vrefid, &size, &bile->map_pos); + /* load map pointer */ + size = sizeof(bile->map_ptr); + _bile_error = FSRead(bile->vrefid, &size, &bile->map_ptr); if (_bile_error) goto open_bail; - - size = sizeof(long); - _bile_error = FSRead(bile->vrefid, &size, &bile->map_size); - if (_bile_error) - goto open_bail; - if (bile->map_pos + bile->map_size > file_size) + if (bile->map_ptr.pos + bile->map_ptr.size > file_size) panic("bile_open: map points to %lu + %lu, but file is only %lu", - bile->map_pos, bile->map_size, file_size); + bile->map_ptr.pos, bile->map_ptr.size, file_size); + if (bile->map_ptr.size % BILE_OBJECT_SIZE != 0) + panic("bile_open: map pointer size is not a multiple of object " + "size (%lu): %lu", BILE_OBJECT_SIZE, bile->map_ptr.size); - if (bile->map_size) { - _bile_error = SetFPos(bile->vrefid, fsFromStart, bile->map_pos + - BILE_OBJECT_SIZE); + if (bile->map_ptr.size) { + /* read and verify map object header map_ptr points to */ + _bile_error = SetFPos(bile->vrefid, fsFromStart, bile->map_ptr.pos); if (_bile_error) goto open_bail; - /* read size */ - size = bile->map_size; - bile->map = xmalloczero(bile->map_size); + size = sizeof(struct bile_object); + _bile_error = FSRead(bile->vrefid, &size, &map_obj); + if (_bile_error) + goto open_bail; + + if (map_obj.pos != bile->map_ptr.pos) + panic("bile_open: map pointer points to %lu but object there " + "has position %lu", bile->map_ptr.pos, map_obj.pos); + if (map_obj.size != bile->map_ptr.size) + panic("bile_open: map is supposed to have size %lu but object " + "pointed to has size %lu", bile->map_ptr.size, map_obj.size); + + /* read entire map */ + size = map_obj.size; + bile->map = xmalloczero(size); _bile_error = FSRead(bile->vrefid, &size, bile->map); if (_bile_error) goto open_bail; - bile->nobjects = bile->map_size / BILE_OBJECT_SIZE; + bile->nobjects = map_obj.size / BILE_OBJECT_SIZE; } return bile; @@ -243,7 +250,7 @@ struct bile_object * bile_alloc(struct bile *bile, const OSType type, const unsigned long id, const size_t size) { - struct bile_object *new, *o; + struct bile_object *newo, *o; size_t last_pos = BILE_HEADER_LEN; short n; @@ -262,12 +269,12 @@ bile_alloc(struct bile *bile, const OSType type, const last_pos = bile->map[n].pos + BILE_OBJECT_SIZE + bile->map[n].size; } - new = &bile->map[bile->nobjects]; + newo = &bile->map[bile->nobjects]; bile->nobjects++; - new->pos = last_pos; - new->size = size; - new->type = type; - new->id = id; + newo->pos = last_pos; + newo->size = size; + newo->type = type; + newo->id = id; bile_sort_by_pos(bile); @@ -321,7 +328,7 @@ bile_delete(struct bile *bile, const OSType type, cons return -1; } - o->type = BILE_PURGE_TYPE; + o->type = BILE_TYPE_PURGE; pos = o->pos; size = o->size + BILE_OBJECT_SIZE; @@ -467,15 +474,14 @@ bile_write(struct bile *bile, const OSType type, const old = bile_find(bile, type, id); if (old) - old->type = BILE_PURGE_TYPE; + old->type = BILE_TYPE_PURGE; new_obj = bile_alloc(bile, type, id, len); - bile_xwriteat(bile, new_obj->pos, BILE_OBJECT_SIZE, new_obj); + bile_xwriteat(bile, new_obj->pos, new_obj, BILE_OBJECT_SIZE); if (_bile_error) return 0; - wrote = bile_xwriteat(bile, new_obj->pos + BILE_OBJECT_SIZE, len, - data); + wrote = bile_xwriteat(bile, new_obj->pos + BILE_OBJECT_SIZE, data, len); if (wrote == 0 || _bile_error) return 0; @@ -493,7 +499,7 @@ short bile_write_map(struct bile *bile) { struct bile_object *obj, *new_map_obj, *new_map; - size_t new_map_size, new_nobjects; + size_t new_map_size, new_nobjects, new_map_id; size_t n; if (bile == NULL) @@ -503,19 +509,25 @@ bile_write_map(struct bile *bile) /* allocate a new map slightly larger than we need */ new_nobjects = bile->nobjects; - if (!bile->map_pos) + if (bile->map_ptr.pos) + new_map_id = bile->map_ptr.id + 1; + else { + /* new file, map never written, allocate another object for map */ new_nobjects++; + new_map_id = 1; + } new_map_size = BILE_OBJECT_SIZE * new_nobjects; - new_map_obj = bile_alloc(bile, BILE_MAP_TYPE, 0, new_map_size); + new_map_obj = bile_alloc(bile, BILE_TYPE_MAP, new_map_id, + new_map_size); new_map = xmallocarray(BILE_OBJECT_SIZE, new_nobjects); for (n = 0, new_nobjects = 0; n < bile->nobjects; n++) { obj = &bile->map[n]; - if (obj->type == BILE_MAP_TYPE && obj->pos == bile->map_pos) + if (obj->type == BILE_TYPE_MAP && obj->pos == bile->map_ptr.pos) /* don't include old map in new one */ continue; - if (obj->type == BILE_PURGE_TYPE) + if (obj->type == BILE_TYPE_PURGE) continue; new_map[new_nobjects++] = *obj; @@ -526,11 +538,14 @@ bile_write_map(struct bile *bile) new_map_obj->size = new_map_size; bile->nobjects = new_nobjects; - bile_xwriteat(bile, new_map_obj->pos, BILE_OBJECT_SIZE, &new_map_obj); + /* write object header */ + bile_xwriteat(bile, new_map_obj->pos, new_map_obj, BILE_OBJECT_SIZE); if (_bile_error) return -1; - bile_xwriteat(bile, new_map_obj->pos + BILE_OBJECT_SIZE, new_map_size, - new_map); + + /* and then the map contents */ + bile_xwriteat(bile, new_map_obj->pos + BILE_OBJECT_SIZE, new_map, + new_map_size); if (_bile_error) return -1; @@ -540,17 +555,15 @@ bile_write_map(struct bile *bile) /* successfully wrote new map, switch over */ free(bile->map); bile->map = new_map; - bile->map_pos = new_map_obj->pos; - bile->map_size = new_map_obj->size; - - /* write new header to point at new map object */ - bile_xwriteat(bile, BILE_MAGIC_LEN, sizeof(long), &bile->map_pos); + bile->map_ptr.pos = new_map_obj->pos; + bile->map_ptr.size = new_map_obj->size; + bile->map_ptr.id = new_map_obj->id; + + /* write new pointer to point at new map object */ + bile_xwriteat(bile, BILE_MAGIC_LEN, &bile->map_ptr, + sizeof(bile->map_ptr)); if (_bile_error) return -1; - bile_xwriteat(bile, BILE_MAGIC_LEN + sizeof(long), sizeof(long), - &bile->map_size); - if (_bile_error) - return -1; /* TODO: flush? */ @@ -558,8 +571,8 @@ bile_write_map(struct bile *bile) } size_t -bile_xwriteat(struct bile *bile, const size_t pos, const size_t len, - const void *data) +bile_xwriteat(struct bile *bile, const size_t pos, const void *data, + const size_t len) { short error; size_t wsize; --- bile.h Wed Jan 5 20:41:23 2022 +++ bile.h Thu Jan 6 16:42:25 2022 @@ -41,9 +41,9 @@ */ #define BILE_MAGIC "BILE1" #define BILE_MAGIC_LEN 5 -#define BILE_HEADER_LEN (BILE_MAGIC_LEN + (sizeof(long) + sizeof(long))) -#define BILE_MAP_TYPE '_BLM' -#define BILE_PURGE_TYPE '_BLP' +#define BILE_TYPE_MAP '_BLM' +#define BILE_TYPE_MAPPTR '_BL>' +#define BILE_TYPE_PURGE '_BLP' struct bile_object { unsigned long pos; @@ -52,15 +52,14 @@ struct bile_object { unsigned long id; }; #define BILE_OBJECT_SIZE (sizeof(struct bile_object)) +#define BILE_HEADER_LEN (BILE_MAGIC_LEN + BILE_OBJECT_SIZE) struct bile { - unsigned long map_pos; - unsigned long map_size; - + struct bile_object map_ptr; short vrefid; Str255 filename; size_t file_size; - struct bile_object *map; + struct bile_object *map; /* array of bile_objects */ size_t nobjects; };