[code cleanup] Improved code readability for getting ID3Tag

Change-Id: I1be3ab6b95a7e0c75e349b6de365769ef8e3944e

diff --git a/formats/ffmpeg/mm_file_format_mp3.c b/formats/ffmpeg/mm_file_format_mp3.c
index 2e3772636ca22fa81b435c04bf6b039c7cb52a8a..4b8fccd43914cc7ee7c13c120fb956b89c49ac36 100644 (file)
--- a/formats/ffmpeg/mm_file_format_mp3.c
+++ b/formats/ffmpeg/mm_file_format_mp3.c
@@ -701,21 +701,38 @@ __AvGetBitrate(AvFileContentInfo *pInfo)
        return true;
 }
 
-static bool __AvGetID3Header(unsigned char *buf, size_t buf_size, AvTagVer2AdditionalData *id3v2info)
+static bool __AvGetID3v1Header(unsigned char *buf, size_t buf_size, int *offset)
+{
+       unsigned char           TagV1ID[4] = { 0x54, 0x41, 0x47}; /* TAG */
+       int id3v1_offset = 0;
+
+       id3v1_offset = __AvMemstr(buf, TagV1ID, 3, TAGV1_SEEK_GAP + 5);
+       if (id3v1_offset < 0) {
+               debug_msg(RELEASE, "ID3v1 is not existing");
+               return false;
+       }
+
+       *offset = id3v1_offset;
+
+       debug_msg(RELEASE, "ID3v1 is existing");
+       return true;
+}
+
+static bool __AvGetID3v2Header(unsigned char *buf, size_t buf_size, AvTagVer2AdditionalData *id3v2info)
 {
        if (!buf || buf_size < MP3_TAGv2_HEADER_LEN || !id3v2info) {
                debug_error(DEBUG, "Invalid parameters!");
                return false;
        }
 
-       if (!IS_ID3V2_TAG(buf)) {
-               debug_error(RELEASE, "Invalid ID3 identifier !");
+       if (!IS_ID3V2_TAG(buf)) { /* ID3 */
+               debug_error(RELEASE, "Invalid ID3v2 identifier !");
                return false;
        }
 
        /* weak id3v2 tag check */
        if (buf[3] == 0xFF || buf[4] == 0xFF || buf[6] >= 0x80 || buf[7] >= 0x80 || buf[8] >= 0x80 || buf[9] >= 0x80) {
-               debug_error(RELEASE, "Invalid ID3 base header!");
+               debug_error(RELEASE, "Invalid ID3v2 base header!");
                return false;
        }
 
@@ -732,7 +749,7 @@ static bool __AvGetID3Header(unsigned char *buf, size_t buf_size, AvTagVer2Addit
        return true;
 }
 
-static int __AvGetLastID3offset(MMFileIOHandle *fp, unsigned int *offset)
+static int __AvGetLastID3v2offset(MMFileIOHandle *fp, unsigned int *offset)
 {
        unsigned char tagHeader[MP3_TAGv2_HEADER_LEN] = {0, };
        unsigned int total_taglen = 0;
@@ -752,7 +769,7 @@ _START_TAG_SEARCH:
                return 0;
        }
 
-       if (!__AvGetID3Header(tagHeader, MP3_TAGv2_HEADER_LEN, &tagInfo)) {
+       if (!__AvGetID3v2Header(tagHeader, MP3_TAGv2_HEADER_LEN, &tagInfo)) {
                debug_msg(RELEASE, "Invalid ID3 header\n");
                goto search_end;
        }
@@ -769,6 +786,46 @@ search_end:
        return 1;
 }
 
+static bool __AvGetID3v1Tags(unsigned char *buf, int offset, AvFileContentInfo *pInfo)
+{
+       unsigned char   TmpBuff[MP3TAGINFO_SIZE] = {0, };
+
+       if (!buf || !pInfo || offset < 0) {
+               debug_error(DEBUG, "Invalid parameters!");
+               return true;
+       }
+
+       if (pInfo->tagV2Info.tagLen != 0 || offset != TAGV1_SEEK_GAP) {
+               debug_msg(RELEASE, "No need to check id3v1");
+               return true;
+       }
+
+       memcpy(TmpBuff, buf, MP3TAGINFO_SIZE);
+
+       return mm_file_id3tag_parse_v110(pInfo, TmpBuff);
+}
+
+static void __AvGetID3v2Tags(unsigned char *buf, AvFileContentInfo *pInfo)
+{
+       if (!buf || !pInfo || pInfo->tagV2Info.tagLen == 0) {
+               debug_error(DEBUG, "Invalid parameters!");
+               return;
+       }
+
+       if (pInfo->tagV2Info.tagVersion == 0x02) {
+               if (!mm_file_id3tag_parse_v222(pInfo, buf))
+                       pInfo->tagV2Info.tagLen = 0;
+       } else if (pInfo->tagV2Info.tagVersion == 0x03) {
+               if (!mm_file_id3tag_parse_v223(pInfo, buf))
+                       pInfo->tagV2Info.tagLen = 0;
+       } else if (pInfo->tagV2Info.tagVersion == 0x04) {
+               if (!mm_file_id3tag_parse_v224(pInfo, buf)) /* currently 2.4 ver pased by 2.3 routine */
+                       pInfo->tagV2Info.tagLen = 0;
+       } else {
+               debug_msg(RELEASE, "Invalid tag version(%d)\n", pInfo->tagV2Info.tagVersion);
+       }
+}
+
 /*
  *     This fuction retrieves the start position of header.
  *     Param   _pFile [in]     Specifies the file pointer of mp3 file.
@@ -795,19 +852,6 @@ __AvFindStartOfMp3Header(MMFileIOHandle *hFile,  unsigned char *buf, AvFileConte
                bufLen = pInfo->fileLen - pInfo->tagV2Info.tagLen;
 
        if (IS_ID3V2_TAG(buf)) {
-               if (pInfo->tagV2Info.tagVersion == 0x02) {
-                       if (!mm_file_id3tag_parse_v222(pInfo, buf))
-                               pInfo->tagV2Info.tagLen = 0;
-               } else if (pInfo->tagV2Info.tagVersion == 0x03) {
-                       if (!mm_file_id3tag_parse_v223(pInfo, buf))
-                               pInfo->tagV2Info.tagLen = 0;
-               } else if (pInfo->tagV2Info.tagVersion == 0x04) {
-                       if (!mm_file_id3tag_parse_v224(pInfo, buf)) /* currently 2.4 ver pased by 2.3 routine */
-                               pInfo->tagV2Info.tagLen = 0;
-               } else {
-                       debug_msg(RELEASE, "pInfo->tagV2Info.tagVersion(%d)\n", pInfo->tagV2Info.tagVersion);
-               }
-
                id3v2TagLen = pInfo->tagV2Info.tagLen;
 
                debug_msg(RELEASE, "id3v2TagLen(%lu)\n", id3v2TagLen);
@@ -966,7 +1010,6 @@ static int mmf_file_mp3_get_infomation(char *filename, AvFileContentInfo *pInfo)
        unsigned char   *v2TagExistCheck = NULL;
        int     readAmount = 0, readedDataLen = 0;
        unsigned char   TagBuff[MP3TAGINFO_SIZE + TAGV1_SEEK_GAP];
-       unsigned char           TagV1ID[4] = { 0x54, 0x41, 0x47}; /*TAG */
        int             tagHeaderPos = 0;
        int ret = 0;
        unsigned int head_offset = 0;
@@ -1004,7 +1047,7 @@ static int mmf_file_mp3_get_infomation(char *filename, AvFileContentInfo *pInfo)
        }
 
        if (mmfile_read(hFile, v2TagExistCheck, MP3_TAGv2_HEADER_LEN) > 0) {
-               __AvGetID3Header(v2TagExistCheck, MP3_TAGv2_HEADER_LEN, &pInfo->tagV2Info);
+               __AvGetID3v2Header(v2TagExistCheck, MP3_TAGv2_HEADER_LEN, &pInfo->tagV2Info);
                mmfile_free(v2TagExistCheck);
        } else {
                debug_error(DEBUG, "v2TagExistCheck value read fail!\n");
@@ -1065,12 +1108,13 @@ static int mmf_file_mp3_get_infomation(char *filename, AvFileContentInfo *pInfo)
                }
        }
 
-
-       if (__AvGetLastID3offset(hFile, &head_offset)) {
+       if (__AvGetLastID3v2offset(hFile, &head_offset)) {
                debug_msg(RELEASE, "search start offset: %u\n", head_offset);
                pInfo->tagV2Info.tagLen = head_offset;
        }
 
+       __AvGetID3v2Tags(buf, pInfo);
+
        pInfo->headerPos = (long) __AvFindStartOfMp3Header(hFile, buf, pInfo);
 
        debug_msg(RELEASE, "Header Pos: %ld\n", pInfo->headerPos);
@@ -1106,18 +1150,10 @@ static int mmf_file_mp3_get_infomation(char *filename, AvFileContentInfo *pInfo)
        if (mmfile_read(hFile, TagBuff, MP3TAGINFO_SIZE + TAGV1_SEEK_GAP) <= 0)
                goto EXCEPTION;
 
-       if ((tagHeaderPos = __AvMemstr(TagBuff, TagV1ID, 3, TAGV1_SEEK_GAP + 5)) >= 0) {
-               debug_msg(RELEASE, "Mp3 File Tag is existing\n");
-
+       if (__AvGetID3v1Header(TagBuff, MP3TAGINFO_SIZE + TAGV1_SEEK_GAP, &tagHeaderPos)) {
                pInfo->bV1tagFound = true;
-               /* In this case, V2 Tag not exist.. So, try to read V1 tag  */
-               if (pInfo->tagV2Info.tagLen == 0 && tagHeaderPos == TAGV1_SEEK_GAP) {
-                       unsigned char   TmpBuff[MP3TAGINFO_SIZE] = {0, };
-
-                       memcpy(TmpBuff, (TagBuff + tagHeaderPos), MP3TAGINFO_SIZE);
-                       if (!mm_file_id3tag_parse_v110(pInfo, TmpBuff))
-                               goto EXCEPTION;
-               }
+               if (!__AvGetID3v1Tags((TagBuff + tagHeaderPos), tagHeaderPos, pInfo))
+                       goto EXCEPTION;
        }
 
        mm_file_id3tag_restore_content_info(pInfo);