log: Support for 256color terminals

And provide extended coloring capabilities for debugging.
The default colors do not change in 256 more to keep
supporting people using Black on White, White on Black and
Solarized terminals.

Signed-off-by: Luca Barbato <lu_zero@gentoo.org>

3 files changed, 47 insertions, 20 deletions

diff --git a/libavutil/log.c b/libavutil/log.c
index 3cc811bccc..c447b5a10f 100644
--- a/libavutil/log.c
+++ b/libavutil/log.c
@@ -53,35 +53,50 @@ static HANDLE con;
 #else
 static const uint8_t color[] = { 0x41, 0x41, 0x11, 0x03, 9, 0x02, 0x06 };
 #define set_color(x)  fprintf(stderr, "\033[%d;3%dm", color[x] >> 4, color[x]&15)
+#define print_256color(x) fprintf(stderr, "\033[38;5;%dm", x)
 #define reset_color() fprintf(stderr, "\033[0m")
 #endif
 static int use_color = -1;
 
-static void colored_fputs(int level, const char *str)
+static void check_color_terminal(void)
 {
-    if (use_color < 0) {
 #if HAVE_SETCONSOLETEXTATTRIBUTE
-        CONSOLE_SCREEN_BUFFER_INFO con_info;
-        con = GetStdHandle(STD_ERROR_HANDLE);
-        use_color = (con != INVALID_HANDLE_VALUE) && !getenv("NO_COLOR") &&
-                    !getenv("AV_LOG_FORCE_NOCOLOR");
-        if (use_color) {
-            GetConsoleScreenBufferInfo(con, &con_info);
-            attr_orig  = con_info.wAttributes;
-            background = attr_orig & 0xF0;
-        }
+    CONSOLE_SCREEN_BUFFER_INFO con_info;
+    con = GetStdHandle(STD_ERROR_HANDLE);
+    use_color = (con != INVALID_HANDLE_VALUE) && !getenv("NO_COLOR") &&
+                !getenv("AV_LOG_FORCE_NOCOLOR");
+    if (use_color) {
+        GetConsoleScreenBufferInfo(con, &con_info);
+        attr_orig  = con_info.wAttributes;
+        background = attr_orig & 0xF0;
+    }
 #elif HAVE_ISATTY
-        use_color = !getenv("NO_COLOR") && !getenv("AV_LOG_FORCE_NOCOLOR") &&
-                    (getenv("TERM") && isatty(2) ||
-                     getenv("AV_LOG_FORCE_COLOR"));
+    char *term = getenv("TERM");
+    use_color = !getenv("NO_COLOR") && !getenv("AV_LOG_FORCE_NOCOLOR") &&
+                (getenv("TERM") && isatty(2) || getenv("AV_LOG_FORCE_COLOR"));
+    use_color += !!strstr(term, "256color") ;
 #else
-        use_color = getenv("AV_LOG_FORCE_COLOR") && !getenv("NO_COLOR") &&
-                   !getenv("AV_LOG_FORCE_NOCOLOR");
+    use_color = getenv("AV_LOG_FORCE_COLOR") && !getenv("NO_COLOR") &&
+               !getenv("AV_LOG_FORCE_NOCOLOR");
 #endif
-    }
+}
 
-    if (use_color) {
+static void colored_fputs(int level, int tint, const char *str)
+{
+    if (use_color < 0)
+        check_color_terminal();
+
+    switch (use_color) {
+    case 1:
+        set_color(level);
+        break;
+    case 2:
         set_color(level);
+        if (tint)
+            print_256color(tint);
+        break;
+    default:
+        break;
     }
     fputs(str, stderr);
     if (use_color) {
@@ -102,6 +117,10 @@ void av_log_default_callback(void *avcl, int level, const char *fmt, va_list vl)
     char line[1024];
     static int is_atty;
     AVClass* avc = avcl ? *(AVClass **) avcl : NULL;
+    int tint = av_clip(level >> 8, 0, 256);
+
+    level &= 0xff;
+
     if (level > av_log_level)
         return;
     line[0] = 0;
@@ -138,7 +157,7 @@ void av_log_default_callback(void *avcl, int level, const char *fmt, va_list vl)
         fprintf(stderr, "    Last message repeated %d times\n", count);
         count = 0;
     }
-    colored_fputs(av_clip(level >> 3, 0, 6), line);
+    colored_fputs(av_clip(level >> 3, 0, 6), tint, line);
     av_strlcpy(prev, line, sizeof line);
 }
 
diff --git a/libavutil/log.h b/libavutil/log.h
index 6d26b67db8..2f7811c072 100644
--- a/libavutil/log.h
+++ b/libavutil/log.h
@@ -144,6 +144,14 @@ typedef struct AVClass {
 #define AV_LOG_DEBUG    48
 
 /**
+ * Sets additional colors for extended debugging sessions.
+ * Requires 256color terminal support. Use outside debugging is not
+ * recommended.
+ */
+
+#define AV_LOG_C(x) (x << 8)
+
+/**
  * @}
  */
 
diff --git a/libavutil/version.h b/libavutil/version.h
index 7f439d725a..f8bb4479e2 100644
--- a/libavutil/version.h
+++ b/libavutil/version.h
@@ -54,7 +54,7 @@
  */
 
 #define LIBAVUTIL_VERSION_MAJOR 53
-#define LIBAVUTIL_VERSION_MINOR  8
+#define LIBAVUTIL_VERSION_MINOR  9
 #define LIBAVUTIL_VERSION_MICRO  0
 
 #define LIBAVUTIL_VERSION_INT   AV_VERSION_INT(LIBAVUTIL_VERSION_MAJOR, \