mp4tagupdate.c

AAC编解码源码

#include <stdlib.h>
#include <string.h>
#include "mp4ffint.h"

#ifdef USE_TAGGING

static uint32_t fix_byte_order_32(uint32_t src)
{
    uint32_t result;
    uint32_t a, b, c, d;
    int8_t data[4];
    
    memcpy(data,&src,sizeof(src));
    a = (uint8_t)data[0];
    b = (uint8_t)data[1];
    c = (uint8_t)data[2];
    d = (uint8_t)data[3];

    result = (a<<24) | (b<<16) | (c<<8) | d;
    return (uint32_t)result;
}

static uint16_t fix_byte_order_16(uint16_t src)
{
    uint16_t result;
    uint16_t a, b;
    int8_t data[2];
    
    memcpy(data,&src,sizeof(src));
    a = (uint8_t)data[0];
    b = (uint8_t)data[1];

    result = (a<<8) | b;
    return (uint16_t)result;
}


typedef struct
{
	void * data;
	unsigned written;
	unsigned allocated;
	unsigned error;
} membuffer;

unsigned membuffer_write(membuffer * buf,const void * ptr,unsigned bytes)
{
	unsigned dest_size = buf->written + bytes;

	if (buf->error) return 0;
	if (dest_size > buf->allocated)
	{
		do
		{
			buf->allocated <<= 1;
		} while(dest_size > buf->allocated);
		
		{
			void * newptr = realloc(buf->data,buf->allocated);
			if (newptr==0)
			{
				free(buf->data);
				buf->data = 0;
				buf->error = 1;
				return 0;
			}
			buf->data = newptr;
		}
	}

	if (ptr) memcpy((char*)buf->data + buf->written,ptr,bytes);
	buf->written += bytes;
	return bytes;
}

#define membuffer_write_data membuffer_write

unsigned membuffer_write_int32(membuffer * buf,uint32_t data)
{
	uint8_t temp[4] = {(uint8_t)(data>>24),(uint8_t)(data>>16),(uint8_t)(data>>8),(uint8_t)data};	
	return membuffer_write_data(buf,temp,4);
}

unsigned membuffer_write_int24(membuffer * buf,uint32_t data)
{
	uint8_t temp[3] = {(uint8_t)(data>>16),(uint8_t)(data>>8),(uint8_t)data};
	return membuffer_write_data(buf,temp,3);
}

unsigned membuffer_write_int16(membuffer * buf,uint16_t data)
{
	uint8_t temp[2] = {(uint8_t)(data>>8),(uint8_t)data};
	return membuffer_write_data(buf,temp,2);
}

unsigned membuffer_write_atom_name(membuffer * buf,const char * data)
{
	return membuffer_write_data(buf,data,4)==4 ? 1 : 0;
}

void membuffer_write_atom(membuffer * buf,const char * name,unsigned size,const void * data)
{
	membuffer_write_int32(buf,size + 8);
	membuffer_write_atom_name(buf,name);
	membuffer_write_data(buf,data,size);
}

unsigned membuffer_write_string(membuffer * buf,const char * data)
{
	return membuffer_write_data(buf,data,strlen(data));
}

unsigned membuffer_write_int8(membuffer * buf,uint8_t data)
{
	return membuffer_write_data(buf,&data,1);
}

void * membuffer_get_ptr(const membuffer * buf)
{
	return buf->data;
}

unsigned membuffer_get_size(const membuffer * buf)
{
	return buf->written;
}

unsigned membuffer_error(const membuffer * buf)
{
	return buf->error;
}

void membuffer_set_error(membuffer * buf) {buf->error = 1;}

unsigned membuffer_transfer_from_file(membuffer * buf,mp4ff_t * src,unsigned bytes)
{
	unsigned oldsize;
	void * bufptr;
	
	oldsize = membuffer_get_size(buf);
	if (membuffer_write_data(buf,0,bytes) != bytes) return 0;

	bufptr = membuffer_get_ptr(buf);
	if (bufptr==0) return 0;
	
	if ((unsigned)mp4ff_read_data(src,(char*)bufptr + oldsize,bytes)!=bytes)
	{
		membuffer_set_error(buf);
		return 0;
	}
	
	return bytes;
}


membuffer * membuffer_create()
{
	const unsigned initial_size = 256;

	membuffer * buf = (membuffer *) malloc(sizeof(membuffer));
	buf->data = malloc(initial_size);
	buf->written = 0;
	buf->allocated = initial_size;
	buf->error = buf->data == 0 ? 1 : 0;

	return buf;
}

void membuffer_free(membuffer * buf)
{
	if (buf->data) free(buf->data);
	free(buf);
}

void * membuffer_detach(membuffer * buf)
{
	void * ret;

	if (buf->error) return 0;

	ret = realloc(buf->data,buf->written);
	
	if (ret == 0) free(buf->data);

	buf->data = 0;
	buf->error = 1;
	
	return ret;
}

#if 0
/* metadata tag structure */
typedef struct
{
    char *item;
    char *value;
} mp4ff_tag_t;

/* metadata list structure */
typedef struct
{
    mp4ff_tag_t *tags;
    uint32_t count;
} mp4ff_metadata_t;
#endif

typedef struct
{
	const char * atom;
	const char * name;	
} stdmeta_entry;

static stdmeta_entry stdmetas[] = 
{
	{"﹏am","title"},
	{"〢RT","artist"},
	{"﹚rt","writer"},
	{"゛lb","album"},
	{"ヾay","date"},
	{"﹖oo","tool"},
	{"ヽmt","comment"},
//	{"ゞen","genre"},
	{"cpil","compilation"},
//	{"trkn","track"},
//	{"disk","disc"},
//	{"gnre","genre"},
	{"covr","cover"},
};


static const char* find_standard_meta(const char * name) //returns atom name if found, 0 if not
{
	unsigned n;
	for(n=0;n<sizeof(stdmetas)/sizeof(stdmetas[0]);n++)
	{
		if (!stricmp(name,stdmetas[n].name)) return stdmetas[n].atom;
	}
    return 0;
}

static void membuffer_write_track_tag(membuffer * buf,const char * name,uint32_t index,uint32_t total)
{
	membuffer_write_int32(buf,8 /*atom header*/ + 8 /*data atom header*/ + 8 /*flags + reserved*/ + 8 /*actual data*/ );
	membuffer_write_atom_name(buf,name);
	membuffer_write_int32(buf,8 /*data atom header*/ + 8 /*flags + reserved*/ + 8 /*actual data*/ );
	membuffer_write_atom_name(buf,"data");
	membuffer_write_int32(buf,0);//flags
	membuffer_write_int32(buf,0);//reserved
	membuffer_write_int16(buf,0);
	membuffer_write_int16(buf,(uint16_t)index);//track number
	membuffer_write_int16(buf,(uint16_t)total);//total tracks
	membuffer_write_int16(buf,0);
}

static void membuffer_write_int16_tag(membuffer * buf,const char * name,uint16_t value)
{
	membuffer_write_int32(buf,8 /*atom header*/ + 8 /*data atom header*/ + 8 /*flags + reserved*/ + 2 /*actual data*/ );
	membuffer_write_atom_name(buf,name);
	membuffer_write_int32(buf,8 /*data atom header*/ + 8 /*flags + reserved*/ + 2 /*actual data*/ );
	membuffer_write_atom_name(buf,"data");
	membuffer_write_int32(buf,0);//flags
	membuffer_write_int32(buf,0);//reserved
	membuffer_write_int16(buf,value);//value
}

static void membuffer_write_std_tag(membuffer * buf,const char * name,const char * value)
{
	membuffer_write_int32(buf,8 /*atom header*/ + 8 /*data atom header*/ + 8 /*flags + reserved*/ + strlen(value) );
	membuffer_write_atom_name(buf,name);
	membuffer_write_int32(buf,8 /*data atom header*/ + 8 /*flags + reserved*/ + strlen(value));
	membuffer_write_atom_name(buf,"data");
	membuffer_write_int32(buf,1);//flags
	membuffer_write_int32(buf,0);//reserved
	membuffer_write_data(buf,value,strlen(value));
}

static void membuffer_write_custom_tag(membuffer * buf,const char * name,const char * value)
{
	membuffer_write_int32(buf,8 /*atom header*/ + 0x1C /*weirdo itunes atom*/ + 12 /*name atom header*/ + strlen(name) + 16 /*data atom header + flags*/ + strlen(value) );
	membuffer_write_atom_name(buf,"----");
	membuffer_write_int32(buf,0x1C);//weirdo itunes atom
	membuffer_write_atom_name(buf,"mean");
	membuffer_write_int32(buf,0);
	membuffer_write_data(buf,"com.apple.iTunes",16);
	membuffer_write_int32(buf,12 + strlen(name));
	membuffer_write_atom_name(buf,"name");
	membuffer_write_int32(buf,0);
	membuffer_write_data(buf,name,strlen(name));
	membuffer_write_int32(buf,8 /*data atom header*/ + 8 /*flags + reserved*/ + strlen(value));
	membuffer_write_atom_name(buf,"data");
	membuffer_write_int32(buf,1);//flags
	membuffer_write_int32(buf,0);//reserved
	membuffer_write_data(buf,value,strlen(value));

}

static uint32_t myatoi(const char * param)
{
	return param ? atoi(param) : 0;
}

static uint32_t create_ilst(const mp4ff_metadata_t * data,void ** out_buffer,uint32_t * out_size)
{
	membuffer * buf = membuffer_create();
	unsigned metaptr;
	char * mask = (char*)malloc(data->count);
	memset(mask,0,data->count);

	{
		const char * tracknumber_ptr = 0, * totaltracks_ptr = 0;
		const char * discnumber_ptr = 0, * totaldiscs_ptr = 0;
		const char * genre_ptr = 0, * tempo_ptr = 0;
		for(metaptr = 0; metaptr < data->count; metaptr++)
		{
			mp4ff_tag_t * tag = &data->tags[metaptr];
			if (!stricmp(tag->item,"tracknumber") || !stricmp(tag->item,"track"))
			{
				if (tracknumber_ptr==0) tracknumber_ptr = tag->value;
				mask[metaptr] = 1;
			}
			else if (!stricmp(tag->item,"totaltracks"))
			{
				if (totaltracks_ptr==0) totaltracks_ptr = tag->value;