add some macros to simplify parsing the config file,

see description in config.h .

They are a variant of the set of macros i used in chan_oss.c,
structured in a way to be more robust to the presence of
spurious ';' - basically, they define wrappers for 'do {'
and '} while (0)', plus some helper functions to deal with simple
cases such as ast_copy_string, ast_malloc, strtoul, ast_true ...

The prefix (CV_ as 'Config Variable') tries to be easy to remember
and has been chosen to not conflict with other existing macros in the tree.

For the time being, I have only updated the three source files in the
tree that used the old M_* macros. Hopefully, more files will be
converted.

NOTE:

    I understand that inventing my own dialect of C is generally wrong;
    however, the lack of adequate support in the language encourages
    lazy programming practices (such as ignoring errors, bounds, etc.)
    and this increases the chance of vulnerability in the code, especially
    because we are parsing user input here.
    Hopefully, these macros and the use of ast_parse_arg (in config.h)
    should encourage the programmer to write more robust code.



git-svn-id: http://svn.digium.com/svn/asterisk/trunk@94191 f38db490-d61c-443f-a65b-d21fe96a405b

1 files changed, 18 insertions, 37 deletions

diff --git a/channels/console_video.c b/channels/console_video.c
index b7a828e90..d59d3bb77 100644
--- a/channels/console_video.c
+++ b/channels/console_video.c
@@ -2987,18 +2987,6 @@ no_sdl:
 		cleanup_sdl(env);
 }
 
-/* see chan_oss.c for these macros */
-#ifndef M_START
-#define _UNDO_M_START
-#define M_START(var, val) \
-        const char *__s = var; const char *__val = val;
-#define M_END(x)		x;
-#define M_F(tag, f)		if (!strcasecmp((__s), tag)) { f; } else
-#define M_BOOL(tag, dst)        M_F(tag, (dst) = ast_true(__val) )
-#define M_UINT(tag, dst)        M_F(tag, (dst) = strtoul(__val, NULL, 0) )
-#define M_STR(tag, dst)         M_F(tag, ast_copy_string(dst, __val, sizeof(dst)))
-#endif
-
 /*
  * Parse a geometry string, accepting also common names for the formats.
  * Trick: if we have a leading > or < and a numeric geometry,
@@ -3245,7 +3233,6 @@ static int console_video_config(struct video_desc **penv,
 	const char *var, const char *val)
 {
 	struct video_desc *env;
-	M_START(var, val);
 
 	if (penv == NULL) {
 		ast_log(LOG_WARNING, "bad argument penv=NULL\n");
@@ -3267,31 +3254,25 @@ static int console_video_config(struct video_desc **penv,
 		env->out.sendvideo = 1;
 		env->out.qmin = 3;
 	}
-        M_STR("videodevice", env->out.videodevice)
-        M_BOOL("sendvideo", env->out.sendvideo)
-        M_F("video_size", video_geom(&env->out.enc_in, val))
-        M_F("camera_size", video_geom(&env->out.loc_src, val))
-        M_F("local_size", video_geom(&env->out.loc_dpy, val))
-        M_F("remote_size", video_geom(&env->in.rem_dpy, val))
-        M_STR("keypad", env->keypad_file)
-        M_F("keypad_entry", keypad_cfg_read(&env->gui, val))
-        M_STR("keypad_mask", env->keypad_mask)
-	M_STR("keypad_font", env->keypad_font)
-        M_UINT("fps", env->out.fps)
-        M_UINT("bitrate", env->out.bitrate)
-        M_UINT("qmin", env->out.qmin)
-	M_STR("videocodec", env->codec_name)
-	M_END(return 1;)	/* the 'nothing found' case */
+	CV_START(var, val);
+        CV_STR("videodevice", env->out.videodevice);
+        CV_BOOL("sendvideo", env->out.sendvideo);
+        CV_F("video_size", video_geom(&env->out.enc_in, val));
+        CV_F("camera_size", video_geom(&env->out.loc_src, val));
+        CV_F("local_size", video_geom(&env->out.loc_dpy, val));
+        CV_F("remote_size", video_geom(&env->in.rem_dpy, val));
+        CV_STR("keypad", env->keypad_file);
+        CV_F("keypad_entry", keypad_cfg_read(&env->gui, val));
+        CV_STR("keypad_mask", env->keypad_mask);
+	CV_STR("keypad_font", env->keypad_font);
+        CV_UINT("fps", env->out.fps);
+        CV_UINT("bitrate", env->out.bitrate);
+        CV_UINT("qmin", env->out.qmin);
+	CV_STR("videocodec", env->codec_name);
+	return 1;	/* nothing found */
+
+	CV_END;		/* the 'nothing found' case */
 	return 0;		/* found something */
 }
-#ifdef _UNDO_M_START
-#undef M_START
-#undef M_END
-#undef M_F
-#undef M_BOOL
-#undef M_UINT
-#undef M_STR
-#undef _UNDO_M_START
-#endif
 
 #endif	/* video support */