Deprecate parse_date() in favor of av_parse_time().

The new av_parse_time() is created in libavutil/parseutils.h, all the
internal functions used by parse_date are moved to
libavutil/parseutils.c and made static.

Signed-off-by: Mans Rullgard <mans@mansr.com>
(cherry picked from commit f6c7375a175ac649558aefab14f3895b2cb469aa)

libavutil/parseutils.c

@@ -22,6 +22,8 @@
  */
 
 #include <strings.h>
+#include <sys/time.h>
+#include <time.h>
 #include "parseutils.h"
 #include "libavutil/avutil.h"
 #include "libavutil/eval.h"
@@ -371,6 +373,241 @@ int av_parse_color(uint8_t *rgba_color, const char *color_string, int slen,
     return 0;
 }
 
+/* get a positive number between n_min and n_max, for a maximum length
+   of len_max. Return -1 if error. */
+static int date_get_num(const char **pp,
+                        int n_min, int n_max, int len_max)
+{
+    int i, val, c;
+    const char *p;
+
+    p = *pp;
+    val = 0;
+    for(i = 0; i < len_max; i++) {
+        c = *p;
+        if (!isdigit(c))
+            break;
+        val = (val * 10) + c - '0';
+        p++;
+    }
+    /* no number read ? */
+    if (p == *pp)
+        return -1;
+    if (val < n_min || val > n_max)
+        return -1;
+    *pp = p;
+    return val;
+}
+
+/* small strptime for ffmpeg */
+static
+const char *small_strptime(const char *p, const char *fmt,
+                           struct tm *dt)
+{
+    int c, val;
+
+    for(;;) {
+        c = *fmt++;
+        if (c == '\0') {
+            return p;
+        } else if (c == '%') {
+            c = *fmt++;
+            switch(c) {
+            case 'H':
+                val = date_get_num(&p, 0, 23, 2);
+                if (val == -1)
+                    return NULL;
+                dt->tm_hour = val;
+                break;
+            case 'M':
+                val = date_get_num(&p, 0, 59, 2);
+                if (val == -1)
+                    return NULL;
+                dt->tm_min = val;
+                break;
+            case 'S':
+                val = date_get_num(&p, 0, 59, 2);
+                if (val == -1)
+                    return NULL;
+                dt->tm_sec = val;
+                break;
+            case 'Y':
+                val = date_get_num(&p, 0, 9999, 4);
+                if (val == -1)
+                    return NULL;
+                dt->tm_year = val - 1900;
+                break;
+            case 'm':
+                val = date_get_num(&p, 1, 12, 2);
+                if (val == -1)
+                    return NULL;
+                dt->tm_mon = val - 1;
+                break;
+            case 'd':
+                val = date_get_num(&p, 1, 31, 2);
+                if (val == -1)
+                    return NULL;
+                dt->tm_mday = val;
+                break;
+            case '%':
+                goto match;
+            default:
+                return NULL;
+            }
+        } else {
+        match:
+            if (c != *p)
+                return NULL;
+            p++;
+        }
+    }
+    return p;
+}
+
+static time_t mktimegm(struct tm *tm)
+{
+    time_t t;
+
+    int y = tm->tm_year + 1900, m = tm->tm_mon + 1, d = tm->tm_mday;
+
+    if (m < 3) {
+        m += 12;
+        y--;
+    }
+
+    t = 86400 *
+        (d + (153 * m - 457) / 5 + 365 * y + y / 4 - y / 100 + y / 400 - 719469);
+
+    t += 3600 * tm->tm_hour + 60 * tm->tm_min + tm->tm_sec;
+
+    return t;
+}
+
+int av_parse_time(int64_t *timeval, const char *datestr, int duration)
+{
+    const char *p;
+    int64_t t;
+    struct tm dt;
+    int i;
+    static const char * const date_fmt[] = {
+        "%Y-%m-%d",
+        "%Y%m%d",
+    };
+    static const char * const time_fmt[] = {
+        "%H:%M:%S",
+        "%H%M%S",
+    };
+    const char *q;
+    int is_utc, len;
+    char lastch;
+    int negative = 0;
+
+#undef time
+    time_t now = time(0);
+
+    len = strlen(datestr);
+    if (len > 0)
+        lastch = datestr[len - 1];
+    else
+        lastch = '\0';
+    is_utc = (lastch == 'z' || lastch == 'Z');
+
+    memset(&dt, 0, sizeof(dt));
+
+    p = datestr;
+    q = NULL;
+    if (!duration) {
+        if (!strncasecmp(datestr, "now", len)) {
+            *timeval = (int64_t) now * 1000000;
+            return 0;
+        }
+
+        /* parse the year-month-day part */
+        for (i = 0; i < FF_ARRAY_ELEMS(date_fmt); i++) {
+            q = small_strptime(p, date_fmt[i], &dt);
+            if (q) {
+                break;
+            }
+        }
+
+        /* if the year-month-day part is missing, then take the
+         * current year-month-day time */
+        if (!q) {
+            if (is_utc) {
+                dt = *gmtime(&now);
+            } else {
+                dt = *localtime(&now);
+            }
+            dt.tm_hour = dt.tm_min = dt.tm_sec = 0;
+        } else {
+            p = q;
+        }
+
+        if (*p == 'T' || *p == 't' || *p == ' ')
+            p++;
+
+        /* parse the hour-minute-second part */
+        for (i = 0; i < FF_ARRAY_ELEMS(time_fmt); i++) {
+            q = small_strptime(p, time_fmt[i], &dt);
+            if (q) {
+                break;
+            }
+        }
+    } else {
+        /* parse datestr as a duration */
+        if (p[0] == '-') {
+            negative = 1;
+            ++p;
+        }
+        /* parse datestr as HH:MM:SS */
+        q = small_strptime(p, time_fmt[0], &dt);
+        if (!q) {
+            /* parse datestr as S+ */
+            dt.tm_sec = strtol(p, (char **)&q, 10);
+            if (q == p) {
+                /* the parsing didn't succeed */
+                *timeval = INT64_MIN;
+                return AVERROR(EINVAL);
+            }
+            dt.tm_min = 0;
+            dt.tm_hour = 0;
+        }
+    }
+
+    /* Now we have all the fields that we can get */
+    if (!q) {
+        *timeval = INT64_MIN;
+        return AVERROR(EINVAL);
+    }
+
+    if (duration) {
+        t = dt.tm_hour * 3600 + dt.tm_min * 60 + dt.tm_sec;
+    } else {
+        dt.tm_isdst = -1;       /* unknown */
+        if (is_utc) {
+            t = mktimegm(&dt);
+        } else {
+            t = mktime(&dt);
+        }
+    }
+
+    t *= 1000000;
+
+    /* parse the .m... part */
+    if (*q == '.') {
+        int val, n;
+        q++;
+        for (val = 0, n = 100000; n >= 1; n /= 10, q++) {
+            if (!isdigit(*q))
+                break;
+            val += n * (*q - '0');
+        }
+        t += val;
+    }
+    *timeval = negative ? -t : t;
+    return 0;
+}
+
 #ifdef TEST
 
 #undef printf