bstr.[ch]: add new files for struct bstr related functionality

Move "struct bstr" definition from ebml.h to its own header and add
some utility functions/macros. Change length field type from int to
size_t and adjust using code accordingly.

Partially based on a patch from Anton Khirnov.

Makefile

@@ -331,6 +331,7 @@ SRCS_COMMON-$(ZR)                    += libmpcodecs/vd_zrmjpeg.c \
                                         libmpcodecs/vf_zrmjpeg.c
 SRCS_COMMON = asxparser.c \
               av_log.c \
+              bstr.c \
               codec-cfg.c \
               cpudetect.c \
               defaultopts.c \

bstr.c

@@ -0,0 +1,51 @@
+/*
+ * This file is part of MPlayer.
+ *
+ * MPlayer is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * MPlayer 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 General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with MPlayer; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+#include <string.h>
+#include <libavutil/avutil.h>
+#include "bstr.h"
+
+int bstrcmp(struct bstr str1, struct bstr str2)
+{
+    int ret = memcmp(str1.start, str2.start, FFMIN(str1.len, str2.len));
+
+    if (!ret) {
+        if (str1.len == str2.len)
+            return 0;
+        else if (str1.len > str2.len)
+            return 1;
+        else
+            return -1;
+    }
+    return ret;
+}
+
+int bstrcasecmp(struct bstr str1, struct bstr str2)
+{
+    int ret = strncasecmp(str1.start, str2.start, FFMIN(str1.len, str2.len));
+
+    if (!ret) {
+        if (str1.len == str2.len)
+            return 0;
+        else if (str1.len > str2.len)
+            return 1;
+        else
+            return -1;
+    }
+    return ret;
+}

bstr.h

@@ -0,0 +1,39 @@
+/*
+ * This file is part of MPlayer.
+ *
+ * MPlayer is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * MPlayer 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 General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with MPlayer; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+#ifndef MPLAYER_BSTR_H
+#define MPLAYER_BSTR_H
+
+#include <stdint.h>
+#include <stddef.h>
+#include <string.h>
+
+struct bstr {
+    const uint8_t *start;
+    size_t len;
+};
+
+int bstrcmp(struct bstr str1, struct bstr str2);
+int bstrcasecmp(struct bstr str1, struct bstr str2);
+
+// Create bstr compound literal from null-terminated string
+#define BSTR(s) (struct bstr){(s), (s) ? strlen(s) : 0}
+// create a pair (not single value!) for "%.*s" printf syntax
+#define BSTR_P(bstr) (int)((bstr).len), (bstr).start
+
+#endif /* MPLAYER_BSTR_H */

libmpdemux/demux_mkv.c

@@ -862,7 +862,7 @@ static int demux_mkv_read_chapters(struct demuxer *demuxer)
                    (int) ((chapter.end / 60 / 1000) % 60),
                    (int) ((chapter.end / 1000) % 60),
                    (int) (chapter.end % 1000),
-                   name.len, name.start);
+                   BSTR_P(name));
 
             if (idx == selected_edition){
                 demuxer_add_chapter(demuxer, name.start, name.len,
@@ -920,7 +920,7 @@ static int demux_mkv_read_attachments(demuxer_t *demuxer)
         demuxer_add_attachment(demuxer, name.start, name.len, mime.start,
                                mime.len, data, data_size);
         mp_msg(MSGT_DEMUX, MSGL_V, "[mkv] Attachment: %.*s, %.*s, %u bytes\n",
-               name.len, name.start, mime.len, mime.start, data_size);
+               BSTR_P(name), BSTR_P(mime), data_size);
     }
 
  out:

libmpdemux/ebml.c

@@ -612,9 +612,9 @@ static void ebml_parse_element(struct ebml_parse_ctx *ctx, void *target,
             strptr->len = length;
             if (ed->type == EBML_TYPE_STR)
                 mp_msg(MSGT_DEMUX, MSGL_DBG2, "string \"%.*s\"\n",
-                       strptr->len, strptr->start);
+                       BSTR_P(*strptr));
             else
-                mp_msg(MSGT_DEMUX, MSGL_DBG2, "binary %d bytes\n",
+                mp_msg(MSGT_DEMUX, MSGL_DBG2, "binary %zd bytes\n",
                        strptr->len);
             break;
 

libmpdemux/ebml.h

@@ -24,6 +24,7 @@
 #include <stdbool.h>
 
 #include "stream/stream.h"
+#include "bstr.h"
 
 
 /* EBML version supported */
@@ -62,11 +63,6 @@ struct ebml_parse_ctx {
     bool no_error_messages;
 };
 
-struct bstr {
-    uint8_t *start;
-    int len;
-};
-
 #include "ebml_types.h"
 
 #define EBML_ID_INVALID 0xffffffff