src/flac/vorbiscomment.c - platform/external/flac - Git at Google

 /* flac - Command-line FLAC encoder/decoder
  * Copyright (C) 2002-2009  Josh Coalson
  * Copyright (C) 2011-2016  Xiph.Org Foundation
  *
  * This program is free software; you can redistribute it and/or
  * modify it under the terms of the GNU General Public License
  * as published by the Free Software Foundation; either version 2
  * of the License, or (at your option) any later version.
  *
  * This program is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  * GNU General Public License for more details.
  *
  * You should have received a copy of the GNU General Public License along
  * with this program; if not, write to the Free Software Foundation, Inc.,
  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  */

 #ifdef HAVE_CONFIG_H
 #  include <config.h>
 #endif

 #include "vorbiscomment.h"
 #include "FLAC/assert.h"
 #include "FLAC/metadata.h"
 #include "share/grabbag.h" /* for grabbag__file_get_filesize() */
 #include "share/utf8.h"
 #include <ctype.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
 #include "share/compat.h"


 /*
  * This struct and the following 4 static functions are copied from
  * ../metaflac/.  Maybe someday there will be a convenience
  * library for Vorbis comment parsing.
  */
 typedef struct {
 	char *field; /* the whole field as passed on the command line, i.e. "NAME=VALUE" */
 	char *field_name;
 	/* according to the vorbis spec, field values can contain \0 so simple C strings are not enough here */
 	uint32_t field_value_length;
 	char *field_value;
 	FLAC__bool field_value_from_file; /* true if field_value holds a filename for the value, false for plain value */
 } Argument_VcField;

 static void die(const char *message)
 {
 	FLAC__ASSERT(0 != message);
 	fprintf(stderr, "ERROR: %s\n", message);
 	exit(1);
 }

 static char *local_strdup(const char *source)
 {
 	char *ret;
 	FLAC__ASSERT(0 != source);
 	if(0 == (ret = strdup(source)))
 		die("out of memory during strdup()");
 	return ret;
 }

 static FLAC__bool parse_vorbis_comment_field(const char *field_ref, char **field, char **name, char **value, uint32_t *length, const char **violation)
 {
 	static const char * const violations[] = {
 		"field name contains invalid character",
 		"field contains no '=' character"
 	};

 	char *p, *q, *s;

 	if(0 != field)
 		*field = local_strdup(field_ref);

 	s = local_strdup(field_ref);

 	if(0 == (p = strchr(s, '='))) {
 		free(s);
 		*violation = violations[1];
 		return false;
 	}
 	*p++ = '\0';

 	for(q = s; *q; q++) {
 		if(*q < 0x20 || *q > 0x7d || *q == 0x3d) {
 			free(s);
 			*violation = violations[0];
 			return false;
 		}
 	}

 	*name = local_strdup(s);
 	*value = local_strdup(p);
 	*length = strlen(p);

 	free(s);
 	return true;
 }

 /* slight modification: no 'filename' arg, and errors are passed back in 'violation' instead of printed to stderr */
 static FLAC__bool set_vc_field(FLAC__StreamMetadata *block, const Argument_VcField *field, FLAC__bool *needs_write, FLAC__bool raw, const char **violation)
 {
 	FLAC__StreamMetadata_VorbisComment_Entry entry;
 	char *converted = NULL;

 	FLAC__ASSERT(0 != block);
 	FLAC__ASSERT(block->type == FLAC__METADATA_TYPE_VORBIS_COMMENT);
 	FLAC__ASSERT(0 != field);
 	FLAC__ASSERT(0 != needs_write);

 	if(field->field_value_from_file) {
 		/* read the file into 'data' */
 		FILE *f = 0;
 		char *data = 0;
 		const FLAC__off_t size = grabbag__file_get_filesize(field->field_value);
 		if(size < 0) {
 			*violation = "can't open file for tag value";
 			return false;
 		}
 		if(size >= 0x100000) { /* magic arbitrary limit, actual format limit is near 16MB */
 			*violation = "file for tag value is too large";
 			return false;
 		}
 		if(0 == (data = malloc(size+1)))
 			die("out of memory allocating tag value");
 		data[size] = '\0';
 		if(0 == (f = flac_fopen(field->field_value, "rb")) || fread(data, 1, size, f) != (size_t)size) {
 			free(data);
 			if(f)
 				fclose(f);
 			*violation = "error while reading file for tag value";
 			return false;
 		}
 		fclose(f);
 		if(strlen(data) != (size_t)size) {
 			free(data);
 			*violation = "file for tag value has embedded NULs";
 			return false;
 		}

 		/* move 'data' into 'converted', converting to UTF-8 if necessary */
 		if(raw) {
 			converted = data;
 		}
 		else if(utf8_encode(data, &converted) >= 0) {
 			free(data);
 		}
 		else {
 			free(data);
 			*violation = "error converting file contents to UTF-8 for tag value";
 			return false;
 		}

 		/* create and entry and append it */
 		if(!FLAC__metadata_object_vorbiscomment_entry_from_name_value_pair(&entry, field->field_name, converted)) {
 			free(converted);
 			*violation = "file for tag value is not valid UTF-8";
 			return false;
 		}
 		free(converted);
 		if(!FLAC__metadata_object_vorbiscomment_append_comment(block, entry, /*copy=*/false)) {
 			*violation = "memory allocation failure";
 			return false;
 		}

 		*needs_write = true;
 		return true;
 	}
 	else {
 		FLAC__bool needs_free = false;
 #ifdef _WIN32 /* everything in UTF-8 already. Must not alter */
 		entry.entry = (FLAC__byte *)field->field;
 #else
 		if(raw) {
 			entry.entry = (FLAC__byte *)field->field;
 		}
 		else if(utf8_encode(field->field, &converted) >= 0) {
 			entry.entry = (FLAC__byte *)converted;
 			needs_free = true;
 		}
 		else {
 			*violation = "error converting comment to UTF-8";
 			return false;
 		}
 #endif
 		entry.length = strlen((const char *)entry.entry);
 		if(!FLAC__format_vorbiscomment_entry_is_legal(entry.entry, entry.length)) {
 			if(needs_free)
 				free(converted);
 			/*
 			 * our previous parsing has already established that the field
 			 * name is OK, so it must be the field value
 			 */
 			*violation = "tag value is not valid UTF-8";
 			return false;
 		}

 		if(!FLAC__metadata_object_vorbiscomment_append_comment(block, entry, /*copy=*/true)) {
 			if(needs_free)
 				free(converted);
 			*violation = "memory allocation failure";
 			return false;
 		}

 		*needs_write = true;
 		if(needs_free)
 			free(converted);
 		return true;
 	}
 }

 /*
  * The rest of the code is novel
  */

 static void free_field(Argument_VcField *obj)
 {
 	if(0 != obj->field)
 		free(obj->field);
 	if(0 != obj->field_name)
 		free(obj->field_name);
 	if(0 != obj->field_value)
 		free(obj->field_value);
 }

 FLAC__bool flac__vorbiscomment_add(FLAC__StreamMetadata *block, const char *comment, FLAC__bool value_from_file, FLAC__bool raw, const char **violation)
 {
 	Argument_VcField parsed;
 	FLAC__bool dummy;

 	FLAC__ASSERT(0 != block);
 	FLAC__ASSERT(block->type == FLAC__METADATA_TYPE_VORBIS_COMMENT);
 	FLAC__ASSERT(0 != comment);

 	memset(&parsed, 0, sizeof(parsed));

 	parsed.field_value_from_file = value_from_file;
 	if(!parse_vorbis_comment_field(comment, &(parsed.field), &(parsed.field_name), &(parsed.field_value), &(parsed.field_value_length), violation)) {
 		free_field(&parsed);
 		return false;
 	}

 	if(parsed.field_value_length > 0 && !set_vc_field(block, &parsed, &dummy, raw, violation)) {
 		free_field(&parsed);
 		return false;
 	}
 	else {
 		free_field(&parsed);
 		return true;
 	}
 }
	/* flac - Command-line FLAC encoder/decoder
	* Copyright (C) 2002-2009 Josh Coalson
	* Copyright (C) 2011-2016 Xiph.Org Foundation
	*
	* This program is free software; you can redistribute it and/or
	* modify it under the terms of the GNU General Public License
	* as published by the Free Software Foundation; either version 2
	* of the License, or (at your option) any later version.
	*
	* This program is distributed in the hope that it will be useful,
	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	* GNU General Public License for more details.
	*
	* You should have received a copy of the GNU General Public License along
	* with this program; if not, write to the Free Software Foundation, Inc.,
	* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
	*/

	#ifdef HAVE_CONFIG_H
	# include <config.h>
	#endif

	#include "vorbiscomment.h"
	#include "FLAC/assert.h"
	#include "FLAC/metadata.h"
	#include "share/grabbag.h" /* for grabbag__file_get_filesize() */
	#include "share/utf8.h"
	#include <ctype.h>
	#include <stdio.h>
	#include <stdlib.h>
	#include <string.h>
	#include "share/compat.h"


	/*
	* This struct and the following 4 static functions are copied from
	* ../metaflac/. Maybe someday there will be a convenience
	* library for Vorbis comment parsing.
	*/
	typedef struct {
	char field; / the whole field as passed on the command line, i.e. "NAME=VALUE" */
	char *field_name;
	/* according to the vorbis spec, field values can contain \0 so simple C strings are not enough here */
	uint32_t field_value_length;
	char *field_value;
	FLAC__bool field_value_from_file; /* true if field_value holds a filename for the value, false for plain value */
	} Argument_VcField;

	static void die(const char *message)
	{
	FLAC__ASSERT(0 != message);
	fprintf(stderr, "ERROR: %s\n", message);
	exit(1);
	}

	static char local_strdup(const char source)
	{
	char *ret;
	FLAC__ASSERT(0 != source);
	if(0 == (ret = strdup(source)))
	die("out of memory during strdup()");
	return ret;
	}

	static FLAC__bool parse_vorbis_comment_field(const char field_ref, char field, char name, char value, uint32_t length, const char **violation)
	{
	static const char * const violations[] = {
	"field name contains invalid character",
	"field contains no '=' character"
	};

	char p, q, *s;

	if(0 != field)
	*field = local_strdup(field_ref);

	s = local_strdup(field_ref);

	if(0 == (p = strchr(s, '='))) {
	free(s);
	*violation = violations[1];
	return false;
	}
	*p++ = '\0';

	for(q = s; *q; q++) {
	if(q < 0x20 \|\| q > 0x7d \|\| *q == 0x3d) {
	free(s);
	*violation = violations[0];
	return false;
	}
	}

	*name = local_strdup(s);
	*value = local_strdup(p);
	*length = strlen(p);

	free(s);
	return true;
	}

	/* slight modification: no 'filename' arg, and errors are passed back in 'violation' instead of printed to stderr */
	static FLAC__bool set_vc_field(FLAC__StreamMetadata block, const Argument_VcField field, FLAC__bool needs_write, FLAC__bool raw, const char *violation)
	{
	FLAC__StreamMetadata_VorbisComment_Entry entry;
	char *converted = NULL;

	FLAC__ASSERT(0 != block);
	FLAC__ASSERT(block->type == FLAC__METADATA_TYPE_VORBIS_COMMENT);
	FLAC__ASSERT(0 != field);
	FLAC__ASSERT(0 != needs_write);

	if(field->field_value_from_file) {
	/* read the file into 'data' */
	FILE *f = 0;
	char *data = 0;
	const FLAC__off_t size = grabbag__file_get_filesize(field->field_value);
	if(size < 0) {
	*violation = "can't open file for tag value";
	return false;
	}
	if(size >= 0x100000) { /* magic arbitrary limit, actual format limit is near 16MB */
	*violation = "file for tag value is too large";
	return false;
	}
	if(0 == (data = malloc(size+1)))
	die("out of memory allocating tag value");
	data[size] = '\0';
	if(0 == (f = flac_fopen(field->field_value, "rb")) \|\| fread(data, 1, size, f) != (size_t)size) {
	free(data);
	if(f)
	fclose(f);
	*violation = "error while reading file for tag value";
	return false;
	}
	fclose(f);
	if(strlen(data) != (size_t)size) {
	free(data);
	*violation = "file for tag value has embedded NULs";
	return false;
	}

	/* move 'data' into 'converted', converting to UTF-8 if necessary */
	if(raw) {
	converted = data;
	}
	else if(utf8_encode(data, &converted) >= 0) {
	free(data);
	}
	else {
	free(data);
	*violation = "error converting file contents to UTF-8 for tag value";
	return false;
	}

	/* create and entry and append it */
	if(!FLAC__metadata_object_vorbiscomment_entry_from_name_value_pair(&entry, field->field_name, converted)) {
	free(converted);
	*violation = "file for tag value is not valid UTF-8";
	return false;
	}
	free(converted);
	if(!FLAC__metadata_object_vorbiscomment_append_comment(block, entry, /copy=/false)) {
	*violation = "memory allocation failure";
	return false;
	}

	*needs_write = true;
	return true;
	}
	else {
	FLAC__bool needs_free = false;
	#ifdef _WIN32 /* everything in UTF-8 already. Must not alter */
	entry.entry = (FLAC__byte *)field->field;
	#else
	if(raw) {
	entry.entry = (FLAC__byte *)field->field;
	}
	else if(utf8_encode(field->field, &converted) >= 0) {
	entry.entry = (FLAC__byte *)converted;
	needs_free = true;
	}
	else {
	*violation = "error converting comment to UTF-8";
	return false;
	}
	#endif
	entry.length = strlen((const char *)entry.entry);
	if(!FLAC__format_vorbiscomment_entry_is_legal(entry.entry, entry.length)) {
	if(needs_free)
	free(converted);
	/*
	* our previous parsing has already established that the field
	* name is OK, so it must be the field value
	*/
	*violation = "tag value is not valid UTF-8";
	return false;
	}

	if(!FLAC__metadata_object_vorbiscomment_append_comment(block, entry, /copy=/true)) {
	if(needs_free)
	free(converted);
	*violation = "memory allocation failure";
	return false;
	}

	*needs_write = true;
	if(needs_free)
	free(converted);
	return true;
	}
	}

	/*
	* The rest of the code is novel
	*/

	static void free_field(Argument_VcField *obj)
	{
	if(0 != obj->field)
	free(obj->field);
	if(0 != obj->field_name)
	free(obj->field_name);
	if(0 != obj->field_value)
	free(obj->field_value);
	}

	FLAC__bool flac__vorbiscomment_add(FLAC__StreamMetadata block, const char comment, FLAC__bool value_from_file, FLAC__bool raw, const char **violation)
	{
	Argument_VcField parsed;
	FLAC__bool dummy;

	FLAC__ASSERT(0 != block);
	FLAC__ASSERT(block->type == FLAC__METADATA_TYPE_VORBIS_COMMENT);
	FLAC__ASSERT(0 != comment);

	memset(&parsed, 0, sizeof(parsed));

	parsed.field_value_from_file = value_from_file;
	if(!parse_vorbis_comment_field(comment, &(parsed.field), &(parsed.field_name), &(parsed.field_value), &(parsed.field_value_length), violation)) {
	free_field(&parsed);
	return false;
	}

	if(parsed.field_value_length > 0 && !set_vc_field(block, &parsed, &dummy, raw, violation)) {
	free_field(&parsed);
	return false;
	}
	else {
	free_field(&parsed);
	return true;
	}
	}