utils.c

            do {
                nd = 0;
                while (isdigit(*p)) {
                    nd = nd * 10 + *p++ - '0';
                }
                c = *p++;
            } while (isdigit(c));

            switch(c) {
            case '%':
                goto addchar;
            case 'd':
                if (percentd_found)
                    goto fail;
                percentd_found = 1;
                snprintf(buf1, sizeof(buf1), "%0*d", nd, number);
                len = strlen(buf1);
                if ((q - buf + len) > buf_size - 1)
                    goto fail;
                memcpy(q, buf1, len);
                q += len;
                break;
            default:
                goto fail;
            }
        } else {
        addchar:
            if ((q - buf) < buf_size - 1)
                *q++ = c;
        }
    }
    if (!percentd_found)
        goto fail;
    *q = '\0';
    return 0;
 fail:
    *q = '\0';
    return -1;
}

static void hex_dump_internal(void *avcl, FILE *f, int level, uint8_t *buf, int size)
{
    int len, i, j, c;
#define PRINT(...) do { if (!f) av_log(avcl, level, __VA_ARGS__); else fprintf(f, __VA_ARGS__); } while(0)

    for(i=0;i<size;i+=16) {
        len = size - i;
        if (len > 16)
            len = 16;
        PRINT("%08x ", i);
        for(j=0;j<16;j++) {
            if (j < len)
                PRINT(" %02x", buf[i+j]);
            else
                PRINT("   ");
        }
        PRINT(" ");
        for(j=0;j<len;j++) {
            c = buf[i+j];
            if (c < ' ' || c > '~')
                c = '.';
            PRINT("%c", c);
        }
        PRINT("\n");
    }
#undef PRINT
}

void av_hex_dump(FILE *f, uint8_t *buf, int size)
{
    hex_dump_internal(NULL, f, 0, buf, size);
}

void av_hex_dump_log(void *avcl, int level, uint8_t *buf, int size)
{
    hex_dump_internal(avcl, NULL, level, buf, size);
}

 //FIXME needs to know the time_base
static void pkt_dump_internal(void *avcl, FILE *f, int level, AVPacket *pkt, int dump_payload)
{
#define PRINT(...) do { if (!f) av_log(avcl, level, __VA_ARGS__); else fprintf(f, __VA_ARGS__); } while(0)
    PRINT("stream #%d:\n", pkt->stream_index);
    PRINT("  keyframe=%d\n", ((pkt->flags & PKT_FLAG_KEY) != 0));
    PRINT("  duration=%0.3f\n", (double)pkt->duration / AV_TIME_BASE);
    /* DTS is _always_ valid after av_read_frame() */
    PRINT("  dts=");
    if (pkt->dts == AV_NOPTS_VALUE)
        PRINT("N/A");
    else
        PRINT("%0.3f", (double)pkt->dts / AV_TIME_BASE);
    /* PTS may not be known if B-frames are present. */
    PRINT("  pts=");
    if (pkt->pts == AV_NOPTS_VALUE)
        PRINT("N/A");
    else
        PRINT("%0.3f", (double)pkt->pts / AV_TIME_BASE);
    PRINT("\n");
    PRINT("  size=%d\n", pkt->size);
#undef PRINT
    if (dump_payload)
        av_hex_dump(f, pkt->data, pkt->size);
}

void av_pkt_dump(FILE *f, AVPacket *pkt, int dump_payload)
{
    pkt_dump_internal(NULL, f, 0, pkt, dump_payload);
}

void av_pkt_dump_log(void *avcl, int level, AVPacket *pkt, int dump_payload)
{
    pkt_dump_internal(avcl, NULL, level, pkt, dump_payload);
}

void url_split(char *proto, int proto_size,
               char *authorization, int authorization_size,
               char *hostname, int hostname_size,
               int *port_ptr,
               char *path, int path_size,
               const char *url)
{
    const char *p, *ls, *at, *col, *brk;

    if (port_ptr)               *port_ptr = -1;
    if (proto_size > 0)         proto[0] = 0;
    if (authorization_size > 0) authorization[0] = 0;
    if (hostname_size > 0)      hostname[0] = 0;
    if (path_size > 0)          path[0] = 0;

    /* parse protocol */
    if ((p = strchr(url, ':'))) {
        av_strlcpy(proto, url, FFMIN(proto_size, p + 1 - url));
        p++; /* skip ':' */
        if (*p == '/') p++;
        if (*p == '/') p++;
    } else {
        /* no protocol means plain filename */
        av_strlcpy(path, url, path_size);
        return;
    }

    /* separate path from hostname */
    ls = strchr(p, '/');
    if(!ls)
        ls = strchr(p, '?');
    if(ls)
        av_strlcpy(path, ls, path_size);
    else
        ls = &p[strlen(p)]; // XXX

    /* the rest is hostname, use that to parse auth/port */
    if (ls != p) {
        /* authorization (user[:pass]@hostname) */
        if ((at = strchr(p, '@')) && at < ls) {
            av_strlcpy(authorization, p,
                       FFMIN(authorization_size, at + 1 - p));
            p = at + 1; /* skip '@' */
        }

        if (*p == '[' && (brk = strchr(p, ']')) && brk < ls) {
            /* [host]:port */
            av_strlcpy(hostname, p + 1,
                       FFMIN(hostname_size, brk - p));
            if (brk[1] == ':' && port_ptr)
                *port_ptr = atoi(brk + 2);
        } else if ((col = strchr(p, ':')) && col < ls) {
            av_strlcpy(hostname, p,
                       FFMIN(col + 1 - p, hostname_size));
            if (port_ptr) *port_ptr = atoi(col + 1);
        } else
            av_strlcpy(hostname, p,
                       FFMIN(ls + 1 - p, hostname_size));
    }
}

char *ff_data_to_hex(char *buff, const uint8_t *src, int s)
{
    int i;
    static const char hex_table[16] = { '0', '1', '2', '3',
                                        '4', '5', '6', '7',
                                        '8', '9', 'A', 'B',
                                        'C', 'D', 'E', 'F' };

    for(i = 0; i < s; i++) {
        buff[i * 2]     = hex_table[src[i] >> 4];
        buff[i * 2 + 1] = hex_table[src[i] & 0xF];
    }

    return buff;
}

void av_set_pts_info(AVStream *s, int pts_wrap_bits,
                     int pts_num, int pts_den)
{
    unsigned int gcd= av_gcd(pts_num, pts_den);
    s->pts_wrap_bits = pts_wrap_bits;
    s->time_base.num = pts_num/gcd;
    s->time_base.den = pts_den/gcd;

    if(gcd>1)
        av_log(NULL, AV_LOG_DEBUG, "st:%d removing common factor %d from timebase\n", s->index, gcd);
}