avf: split off format register and lookup function

1 files changed, 183 insertions, 0 deletions

diff --git a/libavformat/format.c b/libavformat/format.c
new file mode 100644
index 0000000000..3a510cdac3
--- /dev/null
+++ b/libavformat/format.c
@@ -0,0 +1,183 @@
+/*
+ * Format register and lookup
+ * Copyright (c) 2000, 2001, 2002 Fabrice Bellard
+ *
+ * This file is part of Libav.
+ *
+ * Libav is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * Libav is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with Libav; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include "avformat.h"
+#include "internal.h"
+#include "libavutil/avstring.h"
+
+/**
+ * @file
+ * Format register and lookup
+ */
+/** head of registered input format linked list */
+static AVInputFormat *first_iformat = NULL;
+/** head of registered output format linked list */
+static AVOutputFormat *first_oformat = NULL;
+
+AVInputFormat *av_iformat_next(AVInputFormat *f)
+{
+    if (f)
+        return f->next;
+    else
+        return first_iformat;
+}
+
+AVOutputFormat *av_oformat_next(AVOutputFormat *f)
+{
+    if (f)
+        return f->next;
+    else
+        return first_oformat;
+}
+
+void av_register_input_format(AVInputFormat *format)
+{
+    AVInputFormat **p = &first_iformat;
+
+    while (*p != NULL)
+        p = &(*p)->next;
+
+    *p = format;
+    format->next = NULL;
+}
+
+void av_register_output_format(AVOutputFormat *format)
+{
+    AVOutputFormat **p = &first_oformat;
+
+    while (*p != NULL)
+        p = &(*p)->next;
+
+    *p = format;
+    format->next = NULL;
+}
+
+int av_match_ext(const char *filename, const char *extensions)
+{
+    const char *ext, *p;
+    char ext1[32], *q;
+
+    if (!filename)
+        return 0;
+
+    ext = strrchr(filename, '.');
+    if (ext) {
+        ext++;
+        p = extensions;
+        for (;;) {
+            q = ext1;
+            while (*p != '\0' && *p != ','  && q - ext1 < sizeof(ext1) - 1)
+                *q++ = *p++;
+            *q = '\0';
+            if (!av_strcasecmp(ext1, ext))
+                return 1;
+            if (*p == '\0')
+                break;
+            p++;
+        }
+    }
+    return 0;
+}
+
+static int match_format(const char *name, const char *names)
+{
+    const char *p;
+    int len, namelen;
+
+    if (!name || !names)
+        return 0;
+
+    namelen = strlen(name);
+    while ((p = strchr(names, ','))) {
+        len = FFMAX(p - names, namelen);
+        if (!av_strncasecmp(name, names, len))
+            return 1;
+        names = p + 1;
+    }
+    return !av_strcasecmp(name, names);
+}
+
+AVOutputFormat *av_guess_format(const char *short_name, const char *filename,
+                                const char *mime_type)
+{
+    AVOutputFormat *fmt = NULL, *fmt_found;
+    int score_max, score;
+
+    /* specific test for image sequences */
+#if CONFIG_IMAGE2_MUXER
+    if (!short_name && filename &&
+        av_filename_number_test(filename) &&
+        ff_guess_image2_codec(filename) != AV_CODEC_ID_NONE) {
+        return av_guess_format("image2", NULL, NULL);
+    }
+#endif
+    /* Find the proper file type. */
+    fmt_found = NULL;
+    score_max = 0;
+    while ((fmt = av_oformat_next(fmt))) {
+        score = 0;
+        if (fmt->name && short_name && !av_strcasecmp(fmt->name, short_name))
+            score += 100;
+        if (fmt->mime_type && mime_type && !strcmp(fmt->mime_type, mime_type))
+            score += 10;
+        if (filename && fmt->extensions &&
+            av_match_ext(filename, fmt->extensions)) {
+            score += 5;
+        }
+        if (score > score_max) {
+            score_max = score;
+            fmt_found = fmt;
+        }
+    }
+    return fmt_found;
+}
+
+enum AVCodecID av_guess_codec(AVOutputFormat *fmt, const char *short_name,
+                              const char *filename, const char *mime_type,
+                              enum AVMediaType type)
+{
+    if (type == AVMEDIA_TYPE_VIDEO) {
+        enum AVCodecID codec_id = AV_CODEC_ID_NONE;
+
+#if CONFIG_IMAGE2_MUXER
+        if (!strcmp(fmt->name, "image2") || !strcmp(fmt->name, "image2pipe")) {
+            codec_id = ff_guess_image2_codec(filename);
+        }
+#endif
+        if (codec_id == AV_CODEC_ID_NONE)
+            codec_id = fmt->video_codec;
+        return codec_id;
+    } else if (type == AVMEDIA_TYPE_AUDIO)
+        return fmt->audio_codec;
+    else if (type == AVMEDIA_TYPE_SUBTITLE)
+        return fmt->subtitle_codec;
+    else
+        return AV_CODEC_ID_NONE;
+}
+
+AVInputFormat *av_find_input_format(const char *short_name)
+{
+    AVInputFormat *fmt = NULL;
+    while ((fmt = av_iformat_next(fmt)))
+        if (match_format(short_name, fmt->name))
+            return fmt;
+    return NULL;
+}