ref: 1f169e7f213754baab2ec46564a190a0a8852eca
dir: /src/info.c/
/******************************************************************** * * * THIS FILE IS PART OF THE libopusfile SOFTWARE CODEC SOURCE CODE. * * USE, DISTRIBUTION AND REPRODUCTION OF THIS LIBRARY SOURCE IS * * GOVERNED BY A BSD-STYLE SOURCE LICENSE INCLUDED WITH THIS SOURCE * * IN 'COPYING'. PLEASE READ THESE TERMS BEFORE DISTRIBUTING. * * * * THE libopusfile SOURCE CODE IS (C) COPYRIGHT 2012 * * by the Xiph.Org Foundation and contributors http://www.xiph.org/ * * * ********************************************************************/ #ifdef HAVE_CONFIG_H #include "config.h" #endif #include "internal.h" #include <limits.h> #include <string.h> static unsigned op_parse_uint16le(const unsigned char *_data){ return _data[0]|_data[1]<<8; } static int op_parse_int16le(const unsigned char *_data){ int ret; ret=_data[0]|_data[1]<<8; return (ret^0x8000)-0x8000; } static opus_uint32 op_parse_uint32le(const unsigned char *_data){ return _data[0]|(opus_uint32)_data[1]<<8| (opus_uint32)_data[2]<<16|(opus_uint32)_data[3]<<24; } static opus_uint32 op_parse_uint32be(const unsigned char *_data){ return _data[3]|(opus_uint32)_data[2]<<8| (opus_uint32)_data[1]<<16|(opus_uint32)_data[0]<<24; } int opus_head_parse(OpusHead *_head,const unsigned char *_data,size_t _len){ OpusHead head; if(_len<8)return OP_ENOTFORMAT; if(memcmp(_data,"OpusHead",8)!=0)return OP_ENOTFORMAT; if(_len<9)return OP_EBADHEADER; head.version=_data[8]; if(head.version>15)return OP_EVERSION; if(_len<19)return OP_EBADHEADER; head.channel_count=_data[9]; head.pre_skip=op_parse_uint16le(_data+10); head.input_sample_rate=op_parse_uint32le(_data+12); head.output_gain=op_parse_int16le(_data+16); head.mapping_family=_data[18]; if(head.mapping_family==0){ if(head.channel_count<1||head.channel_count>2)return OP_EBADHEADER; if(head.version<=1&&_len>19)return OP_EBADHEADER; head.stream_count=1; head.coupled_count=head.channel_count-1; if(_head!=NULL){ _head->mapping[0]=0; _head->mapping[1]=1; } } else if(head.mapping_family==1){ size_t size; int ci; if(head.channel_count<1||head.channel_count>8)return OP_EBADHEADER; size=21+head.channel_count; if(_len<size||head.version<=1&&_len>size)return OP_EBADHEADER; head.stream_count=_data[19]; if(head.stream_count<1)return OP_EBADHEADER; head.coupled_count=_data[20]; if(head.coupled_count>head.stream_count)return OP_EBADHEADER; for(ci=0;ci<head.channel_count;ci++){ if(_data[21+ci]>=head.stream_count+head.coupled_count &&_data[21+ci]!=255){ return OP_EBADHEADER; } } if(_head!=NULL)memcpy(_head->mapping,_data+21,head.channel_count); } /*General purpose players should not attempt to play back content with channel mapping family 255.*/ else if(head.mapping_family==255)return OP_EIMPL; /*No other channel mapping families are currently defined.*/ else return OP_EBADHEADER; if(_head!=NULL)memcpy(_head,&head,head.mapping-(unsigned char *)&head); return 0; } void opus_tags_init(OpusTags *_tags){ memset(_tags,0,sizeof(*_tags)); } void opus_tags_clear(OpusTags *_tags){ int ci; for(ci=_tags->comments;ci-->0;)_ogg_free(_tags->user_comments[ci]); _ogg_free(_tags->user_comments); _ogg_free(_tags->comment_lengths); _ogg_free(_tags->vendor); } /*Ensure there's room for up to _ncomments comments.*/ static int op_tags_ensure_capacity(OpusTags *_tags,size_t _ncomments){ char **user_comments; int *comment_lengths; size_t size; if(OP_UNLIKELY(_ncomments>=(size_t)INT_MAX))return OP_EFAULT; size=sizeof(*_tags->comment_lengths)*(_ncomments+1); if(size/sizeof(*_tags->comment_lengths)!=_ncomments+1)return OP_EFAULT; comment_lengths=(int *)_ogg_realloc(_tags->comment_lengths,size); if(OP_UNLIKELY(comment_lengths==NULL))return OP_EFAULT; comment_lengths[_ncomments]=0; _tags->comment_lengths=comment_lengths; size=sizeof(*_tags->user_comments)*(_ncomments+1); if(size/sizeof(*_tags->user_comments)!=_ncomments+1)return OP_EFAULT; user_comments=(char **)_ogg_realloc(_tags->user_comments,size); if(OP_UNLIKELY(user_comments==NULL))return OP_EFAULT; user_comments[_ncomments]=NULL; _tags->user_comments=user_comments; return 0; } /*Duplicate a (possibly non-NUL terminated) string with a known length.*/ static char *op_strdup_with_len(const char *_s,size_t _len){ size_t size; char *ret; size=sizeof(*ret)*(_len+1); if(OP_UNLIKELY(size<_len))return NULL; ret=(char *)_ogg_malloc(size); if(OP_LIKELY(ret!=NULL)){ ret=(char *)memcpy(ret,_s,sizeof(*ret)*_len); ret[_len]='\0'; } return ret; } /*The actual implementation of opus_tags_parse(). Unlike the public API, this function requires _tags to already be initialized, modifies its contents before success is guaranteed, and assumes the caller will clear it on error.*/ static int opus_tags_parse_impl(OpusTags *_tags, const unsigned char *_data,size_t _len){ opus_uint32 count; size_t len; int ncomments; int ci; len=_len; if(len<8)return OP_ENOTFORMAT; if(memcmp(_data,"OpusTags",8)!=0)return OP_ENOTFORMAT; if(len<16)return OP_EBADHEADER; _data+=8; len-=8; count=op_parse_uint32le(_data); _data+=4; len-=4; if(count>len)return OP_EBADHEADER; if(_tags!=NULL){ _tags->vendor=op_strdup_with_len((char *)_data,count); if(_tags->vendor==NULL)return OP_EFAULT; } _data+=count; len-=count; if(len<4)return OP_EBADHEADER; count=op_parse_uint32le(_data); _data+=4; len-=4; /*Check to make sure there's minimally sufficient data left in the packet.*/ if(count>len>>2)return OP_EBADHEADER; /*Check for overflow (the API limits this to an int).*/ if(count>(opus_uint32)INT_MAX-1)return OP_EFAULT; if(_tags!=NULL){ int ret; ret=op_tags_ensure_capacity(_tags,count); if(ret<0)return ret; } ncomments=(int)count; for(ci=0;ci<ncomments;ci++){ /*Check to make sure there's minimally sufficient data left in the packet.*/ if((size_t)(ncomments-ci)>len>>2)return OP_EBADHEADER; count=op_parse_uint32le(_data); _data+=4; len-=4; if(count>len)return OP_EBADHEADER; /*Check for overflow (the API limits this to an int).*/ if(count>(opus_uint32)INT_MAX)return OP_EFAULT; if(_tags!=NULL){ _tags->user_comments[ci]=op_strdup_with_len((char *)_data,count); if(_tags->user_comments[ci]==NULL)return OP_EFAULT; _tags->comment_lengths[ci]=(int)count; _tags->comments=ci+1; } _data+=count; len-=count; } return 0; } int opus_tags_parse(OpusTags *_tags,const unsigned char *_data,size_t _len){ if(_tags!=NULL){ OpusTags tags; int ret; opus_tags_init(&tags); ret=opus_tags_parse_impl(&tags,_data,_len); if(ret<0)opus_tags_clear(&tags); else *_tags=*&tags; return ret; } else return opus_tags_parse_impl(NULL,_data,_len); } /*The actual implementation of opus_tags_copy(). Unlike the public API, this function requires _dst to already be initialized, modifies its contents before success is guaranteed, and assumes the caller will clear it on error.*/ static int opus_tags_copy_impl(OpusTags *_dst,const OpusTags *_src){ char *vendor; int ncomments; int ret; int ci; vendor=_src->vendor; _dst->vendor=op_strdup_with_len(vendor,strlen(vendor)); if(OP_UNLIKELY(_dst->vendor==NULL))return OP_EFAULT; ncomments=_src->comments; ret=op_tags_ensure_capacity(_dst,ncomments); if(OP_UNLIKELY(ret<0))return ret; for(ci=0;ci<ncomments;ci++){ int len; len=_src->comment_lengths[ci]; OP_ASSERT(len>=0); _dst->user_comments[ci]=op_strdup_with_len(_src->user_comments[ci],len); if(OP_UNLIKELY(_dst->user_comments[ci]==NULL))return OP_EFAULT; _dst->comment_lengths[ci]=len; _dst->comments=ci+1; } return 0; } int opus_tags_copy(OpusTags *_dst,const OpusTags *_src){ OpusTags dst; int ret; opus_tags_init(&dst); ret=opus_tags_copy_impl(&dst,_src); if(OP_UNLIKELY(ret<0))opus_tags_clear(&dst); else *_dst=*&dst; return 0; } int opus_tags_add(OpusTags *_tags,const char *_tag,const char *_value){ char *comment; int tag_len; int value_len; int ncomments; int ret; ncomments=_tags->comments; ret=op_tags_ensure_capacity(_tags,ncomments+1); if(OP_UNLIKELY(ret<0))return ret; tag_len=strlen(_tag); value_len=strlen(_value); /*+2 for '=' and '\0'.*/ _tags->comment_lengths[ncomments]=0; _tags->user_comments[ncomments]=comment= (char *)_ogg_malloc(sizeof(*comment)*(tag_len+value_len+2)); if(OP_UNLIKELY(comment==NULL))return OP_EFAULT; memcpy(comment,_tag,sizeof(*comment)*tag_len); comment[tag_len]='='; memcpy(comment+tag_len+1,_value,sizeof(*comment)*(value_len+1)); _tags->comment_lengths[ncomments]=tag_len+value_len+1; _tags->comments=ncomments+1; return 0; } int opus_tags_add_comment(OpusTags *_tags,const char *_comment){ int comment_len; int ncomments; int ret; ncomments=_tags->comments; ret=op_tags_ensure_capacity(_tags,ncomments+1); if(OP_UNLIKELY(ret<0))return ret; comment_len=(int)strlen(_comment); _tags->comment_lengths[ncomments]=0; _tags->user_comments[ncomments]=op_strdup_with_len(_comment,comment_len); if(OP_UNLIKELY(_tags->user_comments[ncomments]==NULL))return OP_EFAULT; _tags->comment_lengths[ncomments]=comment_len; _tags->comments=ncomments+1; return 0; } int opus_tagcompare(const char *_tag_name,const char *_comment){ return opus_tagncompare(_tag_name,strlen(_tag_name),_comment); } int opus_tagncompare(const char *_tag_name,int _tag_len,const char *_comment){ int ret; OP_ASSERT(_tag_len>=0); ret=op_strncasecmp(_tag_name,_comment,_tag_len); return ret?ret:'='-_comment[_tag_len]; } const char *opus_tags_query(const OpusTags *_tags,const char *_tag,int _count){ char **user_comments; int tag_len; int found; int ncomments; int ci; tag_len=strlen(_tag); ncomments=_tags->comments; user_comments=_tags->user_comments; found=0; for(ci=0;ci<ncomments;ci++){ if(!opus_tagncompare(_tag,tag_len,user_comments[ci])){ /*We return a pointer to the data, not a copy.*/ if(_count==found++)return user_comments[ci]+tag_len+1; } } /*Didn't find anything.*/ return NULL; } int opus_tags_query_count(const OpusTags *_tags,const char *_tag){ char **user_comments; int tag_len; int found; int ncomments; int ci; tag_len=strlen(_tag); ncomments=_tags->comments; user_comments=_tags->user_comments; found=0; for(ci=0;ci<ncomments;ci++){ if(!opus_tagncompare(_tag,tag_len,user_comments[ci]))found++; } return found; } int opus_tags_get_track_gain(const OpusTags *_tags,int *_gain_q8){ char **comments; int ncomments; int ci; comments=_tags->user_comments; ncomments=_tags->comments; /*Look for the first valid R128_TRACK_GAIN tag and use that.*/ for(ci=0;ci<ncomments;ci++){ if(opus_tagncompare("R128_TRACK_GAIN",15,comments[ci])==0){ char *p; opus_int32 gain_q8; int negative; p=comments[ci]+16; negative=0; if(*p=='-'){ negative=-1; p++; } else if(*p=='+')p++; gain_q8=0; while(*p>='0'&&*p<='9'){ gain_q8=10*gain_q8+*p-'0'; if(gain_q8>32767-negative)break; p++; } /*This didn't look like a signed 16-bit decimal integer. Not a valid R128_TRACK_GAIN tag.*/ if(*p!='\0')continue; *_gain_q8=(int)(gain_q8+negative^negative); return 0; } } return OP_FALSE; } static int op_is_jpeg(const unsigned char *_buf,size_t _buf_sz){ return _buf_sz>=11&&memcmp(_buf,"\xFF\xD8\xFF\xE0",4)==0 &&(_buf[4]<<8|_buf[5])>=16&&memcmp(_buf+6,"JFIF",5)==0; } /*Tries to extract the width, height, bits per pixel, and palette size of a JPEG. On failure, simply leaves its outputs unmodified.*/ static void op_extract_jpeg_params(const unsigned char *_buf,size_t _buf_sz, opus_uint32 *_width,opus_uint32 *_height, opus_uint32 *_depth,opus_uint32 *_colors,int *_has_palette){ if(op_is_jpeg(_buf,_buf_sz)){ size_t offs; offs=2; for(;;){ size_t segment_len; int marker; while(offs<_buf_sz&&_buf[offs]!=0xFF)offs++; while(offs<_buf_sz&&_buf[offs]==0xFF)offs++; marker=_buf[offs]; offs++; /*If we hit EOI* (end of image), or another SOI* (start of image), or SOS (start of scan), then stop now.*/ if(offs>=_buf_sz||(marker>=0xD8&&marker<=0xDA))break; /*RST* (restart markers): skip (no segment length).*/ else if(marker>=0xD0&&marker<=0xD7)continue; /*Read the length of the marker segment.*/ if(_buf_sz-offs<2)break; segment_len=_buf[offs]<<8|_buf[offs+1]; if(segment_len<2||_buf_sz-offs<segment_len)break; if(marker==0xC0||(marker>0xC0&&marker<0xD0&&(marker&3)!=0)){ /*Found a SOFn (start of frame) marker segment:*/ if(segment_len>=8){ *_height=_buf[offs+3]<<8|_buf[offs+4]; *_width=_buf[offs+5]<<8|_buf[offs+6]; *_depth=_buf[offs+2]*_buf[offs+7]; *_colors=0; *_has_palette=0; } break; } /*Other markers: skip the whole marker segment.*/ offs+=segment_len; } } } static int op_is_png(const unsigned char *_buf,size_t _buf_sz){ return _buf_sz>=8&&memcmp(_buf,"\x89PNG\x0D\x0A\x1A\x0A",8)==0; } /*Tries to extract the width, height, bits per pixel, and palette size of a PNG. On failure, simply leaves its outputs unmodified.*/ static void op_extract_png_params(const unsigned char *_buf,size_t _buf_sz, opus_uint32 *_width,opus_uint32 *_height, opus_uint32 *_depth,opus_uint32 *_colors,int *_has_palette){ if(op_is_png(_buf,_buf_sz)){ size_t offs; offs=8; while(_buf_sz-offs>=12){ ogg_uint32_t chunk_len; chunk_len=op_parse_uint32be(_buf+offs); if(chunk_len>_buf_sz-(offs+12))break; else if(chunk_len==13&&memcmp(_buf+offs+4,"IHDR",4)==0){ int color_type; *_width=op_parse_uint32be(_buf+offs+8); *_height=op_parse_uint32be(_buf+offs+12); color_type=_buf[offs+17]; if(color_type==3){ *_depth=24; *_has_palette=1; } else{ int sample_depth; sample_depth=_buf[offs+16]; if(color_type==0)*_depth=sample_depth; else if(color_type==2)*_depth=sample_depth*3; else if(color_type==4)*_depth=sample_depth*2; else if(color_type==6)*_depth=sample_depth*4; *_colors=0; *_has_palette=0; break; } } else if(*_has_palette>0&&memcmp(_buf+offs+4,"PLTE",4)==0){ *_colors=chunk_len/3; break; } offs+=12+chunk_len; } } } static int op_is_gif(const unsigned char *_buf,size_t _buf_sz){ return _buf_sz>=6&&(memcmp(_buf,"GIF87a",6)==0||memcmp(_buf,"GIF89a",6)==0); } /*Tries to extract the width, height, bits per pixel, and palette size of a GIF. On failure, simply leaves its outputs unmodified.*/ static void op_extract_gif_params(const unsigned char *_buf,size_t _buf_sz, opus_uint32 *_width,opus_uint32 *_height, opus_uint32 *_depth,opus_uint32 *_colors,int *_has_palette){ if(op_is_gif(_buf,_buf_sz)&&_buf_sz>=14){ *_width=_buf[6]|_buf[7]<<8; *_height=_buf[8]|_buf[9]<<8; /*libFLAC hard-codes the depth to 24.*/ *_depth=24; *_colors=1<<((_buf[10]&7)+1); *_has_palette=1; } } /*The actual implementation of opus_picture_tag_parse(). Unlike the public API, this function requires _pic to already be initialized, modifies its contents before success is guaranteed, and assumes the caller will clear it on error.*/ static int opus_picture_tag_parse_impl(OpusPictureTag *_pic,const char *_tag, unsigned char *_buf,size_t _buf_sz,size_t _base64_sz){ opus_int32 picture_type; opus_uint32 mime_type_length; char *mime_type; opus_uint32 description_length; char *description; opus_uint32 width; opus_uint32 height; opus_uint32 depth; opus_uint32 colors; opus_uint32 data_length; opus_uint32 file_width; opus_uint32 file_height; opus_uint32 file_depth; opus_uint32 file_colors; int format; int has_palette; int colors_set; size_t i; /*Decode the BASE64 data.*/ for(i=0;i<_base64_sz;i++){ opus_uint32 value; int j; value=0; for(j=0;j<4;j++){ unsigned c; unsigned d; c=(unsigned char)_tag[4*i+j]; if(c=='+')d=62; else if(c=='/')d=63; else if(c>='0'&&c<='9')d=52+c-'0'; else if(c>='a'&&c<='z')d=26+c-'a'; else if(c>='A'&&c<='Z')d=c-'A'; else if(c=='='&&3*i+j>_buf_sz)d=0; else return OP_ENOTFORMAT; value=value<<6|d; } _buf[3*i]=(unsigned char)(value>>16); if(3*i+1<_buf_sz){ _buf[3*i+1]=(unsigned char)(value>>8); if(3*i+2<_buf_sz)_buf[3*i+2]=(unsigned char)value; } } i=0; picture_type=op_parse_uint32be(_buf+i); i+=4; /*Extract the MIME type.*/ mime_type_length=op_parse_uint32be(_buf+i); i+=4; if(mime_type_length>_buf_sz-32)return OP_ENOTFORMAT; mime_type=(char *)_ogg_malloc(sizeof(*_pic->mime_type)*(mime_type_length+1)); if(mime_type==NULL)return OP_EFAULT; memcpy(mime_type,_buf+i,sizeof(*mime_type)*mime_type_length); mime_type[mime_type_length]='\0'; _pic->mime_type=mime_type; i+=mime_type_length; /*Extract the description string.*/ description_length=op_parse_uint32be(_buf+i); i+=4; if(description_length>_buf_sz-mime_type_length-32)return OP_ENOTFORMAT; description= (char *)_ogg_malloc(sizeof(*_pic->mime_type)*(description_length+1)); if(description==NULL)return OP_EFAULT; memcpy(description,_buf+i,sizeof(*description)*description_length); description[description_length]='\0'; _pic->description=description; i+=description_length; /*Extract the remaining fields.*/ width=op_parse_uint32be(_buf+i); i+=4; height=op_parse_uint32be(_buf+i); i+=4; depth=op_parse_uint32be(_buf+i); i+=4; colors=op_parse_uint32be(_buf+i); i+=4; /*If one of these is set, they all must be, but colors==0 is a valid value.*/ colors_set=width!=0||height!=0||depth!=0||colors!=0; if(width==0||height==0||depth==0&&colors_set)return OP_ENOTFORMAT; data_length=op_parse_uint32be(_buf+i); i+=4; if(data_length>_buf_sz-i)return OP_ENOTFORMAT; /*Trim extraneous data so we don't copy it below.*/ _buf_sz=i+data_length; /*Attempt to determine the image format.*/ format=OP_PIC_FORMAT_UNKNOWN; if(mime_type_length==3&&strcmp(mime_type,"-->")==0){ format=OP_PIC_FORMAT_URL; /*Picture type 1 must be a 32x32 PNG.*/ if(picture_type==1&&(width!=0||height!=0)&&(width!=32||height!=32)){ return OP_ENOTFORMAT; } /*Append a terminating NUL for the convenience of our callers.*/ _buf[_buf_sz++]='\0'; } else{ if(mime_type_length==10 &&op_strncasecmp(mime_type,"image/jpeg",mime_type_length)==0){ if(op_is_jpeg(_buf+i,data_length))format=OP_PIC_FORMAT_JPEG; } else if(mime_type_length==9 &&op_strncasecmp(mime_type,"image/png",mime_type_length)==0){ if(op_is_png(_buf+i,data_length))format=OP_PIC_FORMAT_PNG; } else if(mime_type_length==9 &&op_strncasecmp(mime_type,"image/gif",mime_type_length)==0){ if(op_is_gif(_buf+i,data_length))format=OP_PIC_FORMAT_GIF; } else if(mime_type_length==0||(mime_type_length==6 &&op_strncasecmp(mime_type,"image/",mime_type_length)==0)){ if(op_is_jpeg(_buf+i,data_length))format=OP_PIC_FORMAT_JPEG; else if(op_is_png(_buf+i,data_length))format=OP_PIC_FORMAT_PNG; else if(op_is_gif(_buf+i,data_length))format=OP_PIC_FORMAT_GIF; } file_width=file_height=file_depth=file_colors=0; has_palette=-1; switch(format){ case OP_PIC_FORMAT_JPEG:{ op_extract_jpeg_params(_buf+i,data_length, &file_width,&file_height,&file_depth,&file_colors,&has_palette); }break; case OP_PIC_FORMAT_PNG:{ op_extract_png_params(_buf+i,data_length, &file_width,&file_height,&file_depth,&file_colors,&has_palette); }break; case OP_PIC_FORMAT_GIF:{ op_extract_gif_params(_buf+i,data_length, &file_width,&file_height,&file_depth,&file_colors,&has_palette); }break; } if(has_palette>=0){ /*If we successfully extracted these parameters from the image, override any declared values.*/ width=file_width; height=file_height; depth=file_depth; colors=file_colors; } /*Picture type 1 must be a 32x32 PNG.*/ if(picture_type==1&&(format!=OP_PIC_FORMAT_PNG||width!=32||height!=32)){ return OP_ENOTFORMAT; } } /*Adjust _buf_sz instead of using data_length to capture the terminating NUL for URLs.*/ _buf_sz-=i; memmove(_buf,_buf+i,sizeof(*_buf)*_buf_sz); _buf=(unsigned char *)_ogg_realloc(_buf,_buf_sz); if(_buf_sz>0&&_buf==NULL)return OP_EFAULT; _pic->type=picture_type; _pic->width=width; _pic->height=height; _pic->depth=depth; _pic->colors=colors; _pic->data_length=data_length; _pic->data=_buf; _pic->format=format; return 0; } int opus_picture_tag_parse(OpusPictureTag *_pic,const char *_tag){ OpusPictureTag pic; unsigned char *buf; size_t base64_sz; size_t buf_sz; size_t tag_length; int ret; if(opus_tagncompare("METADATA_BLOCK_PICTURE",22,_tag)==0)_tag+=23; /*Figure out how much BASE64-encoded data we have.*/ tag_length=strlen(_tag); if(tag_length&3)return OP_ENOTFORMAT; base64_sz=tag_length>>2; buf_sz=3*base64_sz; if(buf_sz<32)return OP_ENOTFORMAT; if(_tag[tag_length-1]=='=')buf_sz--; if(_tag[tag_length-2]=='=')buf_sz--; if(buf_sz<32)return OP_ENOTFORMAT; /*Allocate an extra byte to allow appending a terminating NUL to URL data.*/ buf=(unsigned char *)_ogg_malloc(sizeof(*buf)*(buf_sz+1)); if(buf==NULL)return OP_EFAULT; opus_picture_tag_init(&pic); ret=opus_picture_tag_parse_impl(&pic,_tag,buf,buf_sz,base64_sz); if(ret<0){ opus_picture_tag_clear(&pic); _ogg_free(buf); } else *_pic=*&pic; return ret; } void opus_picture_tag_init(OpusPictureTag *_pic){ memset(_pic,0,sizeof(*_pic)); } void opus_picture_tag_clear(OpusPictureTag *_pic){ _ogg_free(_pic->description); _ogg_free(_pic->mime_type); _ogg_free(_pic->data); }