cannam@85: /* cannam@85: * libid3tag - ID3 tag manipulation library cannam@85: * Copyright (C) 2000-2004 Underbit Technologies, Inc. cannam@85: * cannam@85: * This program is free software; you can redistribute it and/or modify cannam@85: * it under the terms of the GNU General Public License as published by cannam@85: * the Free Software Foundation; either version 2 of the License, or cannam@85: * (at your option) any later version. cannam@85: * cannam@85: * This program is distributed in the hope that it will be useful, cannam@85: * but WITHOUT ANY WARRANTY; without even the implied warranty of cannam@85: * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the cannam@85: * GNU General Public License for more details. cannam@85: * cannam@85: * You should have received a copy of the GNU General Public License cannam@85: * along with this program; if not, write to the Free Software cannam@85: * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA cannam@85: * cannam@85: * $Id: file.c,v 1.21 2004/01/23 09:41:32 rob Exp $ cannam@85: */ cannam@85: cannam@85: # ifdef HAVE_CONFIG_H cannam@85: # include "config.h" cannam@85: # endif cannam@85: cannam@85: # include "global.h" cannam@85: cannam@85: # include cannam@85: # include cannam@85: # include cannam@85: cannam@85: # ifdef HAVE_UNISTD_H cannam@85: # include cannam@85: # endif cannam@85: cannam@85: # ifdef HAVE_ASSERT_H cannam@85: # include cannam@85: # endif cannam@85: cannam@85: # include "id3tag.h" cannam@85: # include "file.h" cannam@85: # include "tag.h" cannam@85: # include "field.h" cannam@85: cannam@85: struct filetag { cannam@85: struct id3_tag *tag; cannam@85: unsigned long location; cannam@85: id3_length_t length; cannam@85: }; cannam@85: cannam@85: struct id3_file { cannam@85: FILE *iofile; cannam@85: enum id3_file_mode mode; cannam@85: char *path; cannam@85: cannam@85: int flags; cannam@85: cannam@85: struct id3_tag *primary; cannam@85: cannam@85: unsigned int ntags; cannam@85: struct filetag *tags; cannam@85: }; cannam@85: cannam@85: enum { cannam@85: ID3_FILE_FLAG_ID3V1 = 0x0001 cannam@85: }; cannam@85: cannam@85: /* cannam@85: * NAME: query_tag() cannam@85: * DESCRIPTION: check for a tag at a file's current position cannam@85: */ cannam@85: static cannam@85: signed long query_tag(FILE *iofile) cannam@85: { cannam@85: fpos_t save_position; cannam@85: id3_byte_t query[ID3_TAG_QUERYSIZE]; cannam@85: signed long size; cannam@85: cannam@85: if (fgetpos(iofile, &save_position) == -1) cannam@85: return 0; cannam@85: cannam@85: size = id3_tag_query(query, fread(query, 1, sizeof(query), iofile)); cannam@85: cannam@85: if (fsetpos(iofile, &save_position) == -1) cannam@85: return 0; cannam@85: cannam@85: return size; cannam@85: } cannam@85: cannam@85: /* cannam@85: * NAME: read_tag() cannam@85: * DESCRIPTION: read and parse a tag at a file's current position cannam@85: */ cannam@85: static cannam@85: struct id3_tag *read_tag(FILE *iofile, id3_length_t size) cannam@85: { cannam@85: id3_byte_t *data; cannam@85: struct id3_tag *tag = 0; cannam@85: cannam@85: data = malloc(size); cannam@85: if (data) { cannam@85: if (fread(data, size, 1, iofile) == 1) cannam@85: tag = id3_tag_parse(data, size); cannam@85: cannam@85: free(data); cannam@85: } cannam@85: cannam@85: return tag; cannam@85: } cannam@85: cannam@85: /* cannam@85: * NAME: update_primary() cannam@85: * DESCRIPTION: update the primary tag with data from a new tag cannam@85: */ cannam@85: static cannam@85: int update_primary(struct id3_tag *tag, struct id3_tag const *new) cannam@85: { cannam@85: unsigned int i; cannam@85: struct id3_frame *frame; cannam@85: cannam@85: if (new) { cannam@85: if (!(new->extendedflags & ID3_TAG_EXTENDEDFLAG_TAGISANUPDATE)) cannam@85: id3_tag_clearframes(tag); cannam@85: cannam@85: i = 0; cannam@85: while ((frame = id3_tag_findframe(new, 0, i++))) { cannam@85: if (id3_tag_attachframe(tag, frame) == -1) cannam@85: return -1; cannam@85: } cannam@85: } cannam@85: cannam@85: return 0; cannam@85: } cannam@85: cannam@85: /* cannam@85: * NAME: tag_compare() cannam@85: * DESCRIPTION: tag sort function for qsort() cannam@85: */ cannam@85: static cannam@85: int tag_compare(const void *a, const void *b) cannam@85: { cannam@85: struct filetag const *tag1 = a, *tag2 = b; cannam@85: cannam@85: if (tag1->location < tag2->location) cannam@85: return -1; cannam@85: else if (tag1->location > tag2->location) cannam@85: return +1; cannam@85: cannam@85: return 0; cannam@85: } cannam@85: cannam@85: /* cannam@85: * NAME: add_filetag() cannam@85: * DESCRIPTION: add a new file tag entry cannam@85: */ cannam@85: static cannam@85: int add_filetag(struct id3_file *file, struct filetag const *filetag) cannam@85: { cannam@85: struct filetag *tags; cannam@85: cannam@85: tags = realloc(file->tags, (file->ntags + 1) * sizeof(*tags)); cannam@85: if (tags == 0) cannam@85: return -1; cannam@85: cannam@85: file->tags = tags; cannam@85: file->tags[file->ntags++] = *filetag; cannam@85: cannam@85: /* sort tags by location */ cannam@85: cannam@85: if (file->ntags > 1) cannam@85: qsort(file->tags, file->ntags, sizeof(file->tags[0]), tag_compare); cannam@85: cannam@85: return 0; cannam@85: } cannam@85: cannam@85: /* cannam@85: * NAME: del_filetag() cannam@85: * DESCRIPTION: delete a file tag entry cannam@85: */ cannam@85: static cannam@85: void del_filetag(struct id3_file *file, unsigned int index) cannam@85: { cannam@85: assert(index < file->ntags); cannam@85: cannam@85: while (index < file->ntags - 1) { cannam@85: file->tags[index] = file->tags[index + 1]; cannam@85: ++index; cannam@85: } cannam@85: cannam@85: --file->ntags; cannam@85: } cannam@85: cannam@85: /* cannam@85: * NAME: add_tag() cannam@85: * DESCRIPTION: read, parse, and add a tag to a file structure cannam@85: */ cannam@85: static cannam@85: struct id3_tag *add_tag(struct id3_file *file, id3_length_t length) cannam@85: { cannam@85: long location; cannam@85: unsigned int i; cannam@85: struct filetag filetag; cannam@85: struct id3_tag *tag; cannam@85: cannam@85: location = ftell(file->iofile); cannam@85: if (location == -1) cannam@85: return 0; cannam@85: cannam@85: /* check for duplication/overlap */ cannam@85: { cannam@85: unsigned long begin1, end1, begin2, end2; cannam@85: cannam@85: begin1 = location; cannam@85: end1 = begin1 + length; cannam@85: cannam@85: for (i = 0; i < file->ntags; ++i) { cannam@85: begin2 = file->tags[i].location; cannam@85: end2 = begin2 + file->tags[i].length; cannam@85: cannam@85: if (begin1 == begin2 && end1 == end2) cannam@85: return file->tags[i].tag; /* duplicate */ cannam@85: cannam@85: if (begin1 < end2 && end1 > begin2) cannam@85: return 0; /* overlap */ cannam@85: } cannam@85: } cannam@85: cannam@85: tag = read_tag(file->iofile, length); cannam@85: cannam@85: filetag.tag = tag; cannam@85: filetag.location = location; cannam@85: filetag.length = length; cannam@85: cannam@85: if (add_filetag(file, &filetag) == -1 || cannam@85: update_primary(file->primary, tag) == -1) { cannam@85: if (tag) cannam@85: id3_tag_delete(tag); cannam@85: return 0; cannam@85: } cannam@85: cannam@85: if (tag) cannam@85: id3_tag_addref(tag); cannam@85: cannam@85: return tag; cannam@85: } cannam@85: cannam@85: /* cannam@85: * NAME: search_tags() cannam@85: * DESCRIPTION: search for tags in a file cannam@85: */ cannam@85: static cannam@85: int search_tags(struct id3_file *file) cannam@85: { cannam@85: fpos_t save_position; cannam@85: signed long size; cannam@85: cannam@85: /* cannam@85: * save the current seek position cannam@85: * cannam@85: * We also verify the stream is seekable by calling fsetpos(), since cannam@85: * fgetpos() alone is not reliable enough for this purpose. cannam@85: * cannam@85: * [Apparently not even fsetpos() is sufficient under Win32.] cannam@85: */ cannam@85: cannam@85: if (fgetpos(file->iofile, &save_position) == -1 || cannam@85: fsetpos(file->iofile, &save_position) == -1) cannam@85: return -1; cannam@85: cannam@85: /* look for an ID3v1 tag */ cannam@85: cannam@85: if (fseek(file->iofile, -128, SEEK_END) == 0) { cannam@85: size = query_tag(file->iofile); cannam@85: if (size > 0) { cannam@85: struct id3_tag const *tag; cannam@85: cannam@85: tag = add_tag(file, size); cannam@85: cannam@85: /* if this is indeed an ID3v1 tag, mark the file so */ cannam@85: cannam@85: if (tag && (ID3_TAG_VERSION_MAJOR(id3_tag_version(tag)) == 1)) cannam@85: file->flags |= ID3_FILE_FLAG_ID3V1; cannam@85: } cannam@85: } cannam@85: cannam@85: /* look for a tag at the beginning of the file */ cannam@85: cannam@85: rewind(file->iofile); cannam@85: cannam@85: size = query_tag(file->iofile); cannam@85: if (size > 0) { cannam@85: struct id3_tag const *tag; cannam@85: struct id3_frame const *frame; cannam@85: cannam@85: tag = add_tag(file, size); cannam@85: cannam@85: /* locate tags indicated by SEEK frames */ cannam@85: cannam@85: while (tag && (frame = id3_tag_findframe(tag, "SEEK", 0))) { cannam@85: long seek; cannam@85: cannam@85: seek = id3_field_getint(id3_frame_field(frame, 0)); cannam@85: if (seek < 0 || fseek(file->iofile, seek, SEEK_CUR) == -1) cannam@85: break; cannam@85: cannam@85: size = query_tag(file->iofile); cannam@85: tag = (size > 0) ? add_tag(file, size) : 0; cannam@85: } cannam@85: } cannam@85: cannam@85: /* look for a tag at the end of the file (before any ID3v1 tag) */ cannam@85: cannam@85: if (fseek(file->iofile, ((file->flags & ID3_FILE_FLAG_ID3V1) ? -128 : 0) + cannam@85: -10, SEEK_END) == 0) { cannam@85: size = query_tag(file->iofile); cannam@85: if (size < 0 && fseek(file->iofile, size, SEEK_CUR) == 0) { cannam@85: size = query_tag(file->iofile); cannam@85: if (size > 0) cannam@85: add_tag(file, size); cannam@85: } cannam@85: } cannam@85: cannam@85: clearerr(file->iofile); cannam@85: cannam@85: /* restore seek position */ cannam@85: cannam@85: if (fsetpos(file->iofile, &save_position) == -1) cannam@85: return -1; cannam@85: cannam@85: /* set primary tag options and target padded length for convenience */ cannam@85: cannam@85: if ((file->ntags > 0 && !(file->flags & ID3_FILE_FLAG_ID3V1)) || cannam@85: (file->ntags > 1 && (file->flags & ID3_FILE_FLAG_ID3V1))) { cannam@85: if (file->tags[0].location == 0) cannam@85: id3_tag_setlength(file->primary, file->tags[0].length); cannam@85: else cannam@85: id3_tag_options(file->primary, ID3_TAG_OPTION_APPENDEDTAG, ~0); cannam@85: } cannam@85: cannam@85: return 0; cannam@85: } cannam@85: cannam@85: /* cannam@85: * NAME: finish_file() cannam@85: * DESCRIPTION: release memory associated with a file cannam@85: */ cannam@85: static cannam@85: void finish_file(struct id3_file *file) cannam@85: { cannam@85: unsigned int i; cannam@85: cannam@85: if (file->path) cannam@85: free(file->path); cannam@85: cannam@85: if (file->primary) { cannam@85: id3_tag_delref(file->primary); cannam@85: id3_tag_delete(file->primary); cannam@85: } cannam@85: cannam@85: for (i = 0; i < file->ntags; ++i) { cannam@85: struct id3_tag *tag; cannam@85: cannam@85: tag = file->tags[i].tag; cannam@85: if (tag) { cannam@85: id3_tag_delref(tag); cannam@85: id3_tag_delete(tag); cannam@85: } cannam@85: } cannam@85: cannam@85: if (file->tags) cannam@85: free(file->tags); cannam@85: cannam@85: free(file); cannam@85: } cannam@85: cannam@85: /* cannam@85: * NAME: new_file() cannam@85: * DESCRIPTION: create a new file structure and load tags cannam@85: */ cannam@85: static cannam@85: struct id3_file *new_file(FILE *iofile, enum id3_file_mode mode, cannam@85: char const *path) cannam@85: { cannam@85: struct id3_file *file; cannam@85: cannam@85: file = malloc(sizeof(*file)); cannam@85: if (file == 0) cannam@85: goto fail; cannam@85: cannam@85: file->iofile = iofile; cannam@85: file->mode = mode; cannam@85: file->path = path ? strdup(path) : 0; cannam@85: cannam@85: file->flags = 0; cannam@85: cannam@85: file->ntags = 0; cannam@85: file->tags = 0; cannam@85: cannam@85: file->primary = id3_tag_new(); cannam@85: if (file->primary == 0) cannam@85: goto fail; cannam@85: cannam@85: id3_tag_addref(file->primary); cannam@85: cannam@85: /* load tags from the file */ cannam@85: cannam@85: if (search_tags(file) == -1) cannam@85: goto fail; cannam@85: cannam@85: id3_tag_options(file->primary, ID3_TAG_OPTION_ID3V1, cannam@85: (file->flags & ID3_FILE_FLAG_ID3V1) ? ~0 : 0); cannam@85: cannam@85: if (0) { cannam@85: fail: cannam@85: if (file) { cannam@85: finish_file(file); cannam@85: file = 0; cannam@85: } cannam@85: } cannam@85: cannam@85: return file; cannam@85: } cannam@85: cannam@85: /* cannam@85: * NAME: file->open() cannam@85: * DESCRIPTION: open a file given its pathname cannam@85: */ cannam@85: struct id3_file *id3_file_open(char const *path, enum id3_file_mode mode) cannam@85: { cannam@85: FILE *iofile; cannam@85: struct id3_file *file; cannam@85: cannam@85: assert(path); cannam@85: cannam@85: iofile = fopen(path, (mode == ID3_FILE_MODE_READWRITE) ? "r+b" : "rb"); cannam@85: if (iofile == 0) cannam@85: return 0; cannam@85: cannam@85: file = new_file(iofile, mode, path); cannam@85: if (file == 0) cannam@85: fclose(iofile); cannam@85: cannam@85: return file; cannam@85: } cannam@85: cannam@85: /* cannam@85: * NAME: file->fdopen() cannam@85: * DESCRIPTION: open a file using an existing file descriptor cannam@85: */ cannam@85: struct id3_file *id3_file_fdopen(int fd, enum id3_file_mode mode) cannam@85: { cannam@85: # if 1 || defined(HAVE_UNISTD_H) cannam@85: FILE *iofile; cannam@85: struct id3_file *file; cannam@85: cannam@85: iofile = fdopen(fd, (mode == ID3_FILE_MODE_READWRITE) ? "r+b" : "rb"); cannam@85: if (iofile == 0) cannam@85: return 0; cannam@85: cannam@85: file = new_file(iofile, mode, 0); cannam@85: if (file == 0) { cannam@85: int save_fd; cannam@85: cannam@85: /* close iofile without closing fd */ cannam@85: cannam@85: save_fd = dup(fd); cannam@85: cannam@85: fclose(iofile); cannam@85: cannam@85: dup2(save_fd, fd); cannam@85: close(save_fd); cannam@85: } cannam@85: cannam@85: return file; cannam@85: # else cannam@85: return 0; cannam@85: # endif cannam@85: } cannam@85: cannam@85: /* cannam@85: * NAME: file->close() cannam@85: * DESCRIPTION: close a file and delete its associated tags cannam@85: */ cannam@85: int id3_file_close(struct id3_file *file) cannam@85: { cannam@85: int result = 0; cannam@85: cannam@85: assert(file); cannam@85: cannam@85: if (fclose(file->iofile) == EOF) cannam@85: result = -1; cannam@85: cannam@85: finish_file(file); cannam@85: cannam@85: return result; cannam@85: } cannam@85: cannam@85: /* cannam@85: * NAME: file->tag() cannam@85: * DESCRIPTION: return the primary tag structure for a file cannam@85: */ cannam@85: struct id3_tag *id3_file_tag(struct id3_file const *file) cannam@85: { cannam@85: assert(file); cannam@85: cannam@85: return file->primary; cannam@85: } cannam@85: cannam@85: /* cannam@85: * NAME: v1_write() cannam@85: * DESCRIPTION: write ID3v1 tag modifications to a file cannam@85: */ cannam@85: static cannam@85: int v1_write(struct id3_file *file, cannam@85: id3_byte_t const *data, id3_length_t length) cannam@85: { cannam@85: assert(!data || length == 128); cannam@85: cannam@85: if (data) { cannam@85: long location; cannam@85: cannam@85: if (fseek(file->iofile, (file->flags & ID3_FILE_FLAG_ID3V1) ? -128 : 0, cannam@85: SEEK_END) == -1 || cannam@85: (location = ftell(file->iofile)) == -1 || cannam@85: fwrite(data, 128, 1, file->iofile) != 1 || cannam@85: fflush(file->iofile) == EOF) cannam@85: return -1; cannam@85: cannam@85: /* add file tag reference */ cannam@85: cannam@85: if (!(file->flags & ID3_FILE_FLAG_ID3V1)) { cannam@85: struct filetag filetag; cannam@85: cannam@85: filetag.tag = 0; cannam@85: filetag.location = location; cannam@85: filetag.length = 128; cannam@85: cannam@85: if (add_filetag(file, &filetag) == -1) cannam@85: return -1; cannam@85: cannam@85: file->flags |= ID3_FILE_FLAG_ID3V1; cannam@85: } cannam@85: } cannam@85: # if defined(HAVE_FTRUNCATE) cannam@85: else if (file->flags & ID3_FILE_FLAG_ID3V1) { cannam@85: long length; cannam@85: cannam@85: if (fseek(file->iofile, 0, SEEK_END) == -1) cannam@85: return -1; cannam@85: cannam@85: length = ftell(file->iofile); cannam@85: if (length == -1 || cannam@85: (length >= 0 && length < 128)) cannam@85: return -1; cannam@85: cannam@85: if (ftruncate(fileno(file->iofile), length - 128) == -1) cannam@85: return -1; cannam@85: cannam@85: /* delete file tag reference */ cannam@85: cannam@85: del_filetag(file, file->ntags - 1); cannam@85: cannam@85: file->flags &= ~ID3_FILE_FLAG_ID3V1; cannam@85: } cannam@85: # endif cannam@85: cannam@85: return 0; cannam@85: } cannam@85: cannam@85: /* cannam@85: * NAME: v2_write() cannam@85: * DESCRIPTION: write ID3v2 tag modifications to a file cannam@85: */ cannam@85: static cannam@85: int v2_write(struct id3_file *file, cannam@85: id3_byte_t const *data, id3_length_t length) cannam@85: { cannam@85: assert(!data || length > 0); cannam@85: cannam@85: if (data && cannam@85: ((file->ntags == 1 && !(file->flags & ID3_FILE_FLAG_ID3V1)) || cannam@85: (file->ntags == 2 && (file->flags & ID3_FILE_FLAG_ID3V1))) && cannam@85: file->tags[0].length == length) { cannam@85: /* easy special case: rewrite existing tag in-place */ cannam@85: cannam@85: if (fseek(file->iofile, file->tags[0].location, SEEK_SET) == -1 || cannam@85: fwrite(data, length, 1, file->iofile) != 1 || cannam@85: fflush(file->iofile) == EOF) cannam@85: return -1; cannam@85: cannam@85: goto done; cannam@85: } cannam@85: cannam@85: /* hard general case: rewrite entire file */ cannam@85: cannam@85: /* ... */ cannam@85: cannam@85: done: cannam@85: return 0; cannam@85: } cannam@85: cannam@85: /* cannam@85: * NAME: file->update() cannam@85: * DESCRIPTION: rewrite tag(s) to a file cannam@85: */ cannam@85: int id3_file_update(struct id3_file *file) cannam@85: { cannam@85: int options, result = 0; cannam@85: id3_length_t v1size = 0, v2size = 0; cannam@85: id3_byte_t id3v1_data[128], *id3v1 = 0, *id3v2 = 0; cannam@85: cannam@85: assert(file); cannam@85: cannam@85: if (file->mode != ID3_FILE_MODE_READWRITE) cannam@85: return -1; cannam@85: cannam@85: options = id3_tag_options(file->primary, 0, 0); cannam@85: cannam@85: /* render ID3v1 */ cannam@85: cannam@85: if (options & ID3_TAG_OPTION_ID3V1) { cannam@85: v1size = id3_tag_render(file->primary, 0); cannam@85: if (v1size) { cannam@85: assert(v1size == sizeof(id3v1_data)); cannam@85: cannam@85: v1size = id3_tag_render(file->primary, id3v1_data); cannam@85: if (v1size) { cannam@85: assert(v1size == sizeof(id3v1_data)); cannam@85: id3v1 = id3v1_data; cannam@85: } cannam@85: } cannam@85: } cannam@85: cannam@85: /* render ID3v2 */ cannam@85: cannam@85: id3_tag_options(file->primary, ID3_TAG_OPTION_ID3V1, 0); cannam@85: cannam@85: v2size = id3_tag_render(file->primary, 0); cannam@85: if (v2size) { cannam@85: id3v2 = malloc(v2size); cannam@85: if (id3v2 == 0) cannam@85: goto fail; cannam@85: cannam@85: v2size = id3_tag_render(file->primary, id3v2); cannam@85: if (v2size == 0) { cannam@85: free(id3v2); cannam@85: id3v2 = 0; cannam@85: } cannam@85: } cannam@85: cannam@85: /* write tags */ cannam@85: cannam@85: if (v2_write(file, id3v2, v2size) == -1 || cannam@85: v1_write(file, id3v1, v1size) == -1) cannam@85: goto fail; cannam@85: cannam@85: rewind(file->iofile); cannam@85: cannam@85: /* update file tags array? ... */ cannam@85: cannam@85: if (0) { cannam@85: fail: cannam@85: result = -1; cannam@85: } cannam@85: cannam@85: /* clean up; restore tag options */ cannam@85: cannam@85: if (id3v2) cannam@85: free(id3v2); cannam@85: cannam@85: id3_tag_options(file->primary, ~0, options); cannam@85: cannam@85: return result; cannam@85: }