[PATCH 3/5] Change ff_parse_expr() and ff_parse_and_eval_expr() interface.

Stefano Sabatini stefano.sabatini-lala
Tue Apr 6 00:13:04 CEST 2010


Make them print error messages using a log_ctx rather than set a
constant error string in the Parser.

Allow the error message to be more expressive, as it is not anymore a
generic const char * string, and reference the provided input.
---
 libavcodec/eval.c        |   20 +++++++++++---------
 libavcodec/eval.h        |    8 ++++----
 libavcodec/opt.c         |    8 ++++----
 libavcodec/ratecontrol.c |    6 +++---
 4 files changed, 22 insertions(+), 20 deletions(-)

diff --git a/libavcodec/eval.c b/libavcodec/eval.c
index 0eadf1c..8d0b8b4 100644
--- a/libavcodec/eval.c
+++ b/libavcodec/eval.c
@@ -39,7 +39,7 @@ typedef struct Parser{
     double (* const *func2)(void *, double a, double b); // NULL terminated
     const char * const *func2_name;          // NULL terminated
     void *opaque;
-    const char **error;
+    void *log_ctx;
 #define VARS 10
     double var[VARS];
 } Parser;
@@ -201,7 +201,7 @@ static AVExpr * parse_primary(Parser *p) {
 
     p->s= strchr(p->s, '(');
     if(p->s==NULL){
-        *p->error = "undefined constant or missing (";
+        av_log(p->log_ctx, AV_LOG_ERROR, "undefined constant or missing (\n");
         p->s= next;
         ff_free_expr(d);
         return NULL;
@@ -211,7 +211,7 @@ static AVExpr * parse_primary(Parser *p) {
         av_freep(&d);
         d = parse_expr(p);
         if(p->s[0] != ')'){
-            *p->error = "missing )";
+            av_log(p->log_ctx, AV_LOG_ERROR, "missing )\n");
             ff_free_expr(d);
             return NULL;
         }
@@ -224,7 +224,7 @@ static AVExpr * parse_primary(Parser *p) {
         d->param[1] = parse_expr(p);
     }
     if(p->s[0] != ')'){
-        *p->error = "missing )";
+        av_log(p->log_ctx, AV_LOG_ERROR, "missing )\n");
         ff_free_expr(d);
         return NULL;
     }
@@ -273,7 +273,7 @@ static AVExpr * parse_primary(Parser *p) {
             }
         }
 
-        *p->error = "unknown function";
+        av_log(p->log_ctx, AV_LOG_ERROR, "unknown function\n");
         ff_free_expr(d);
         return NULL;
     }
@@ -373,7 +373,8 @@ AVExpr *ff_parse_expr(const char *s,
                       const char * const *const_name,
                       const char * const *func1_name, double (* const *func1)(void *, double),
                       const char * const *func2_name, double (* const *func2)(void *, double, double),
-               const char **error){
+                      void *log_ctx)
+{
     Parser p;
     AVExpr *e = NULL;
     char *w = av_malloc(strlen(s) + 1);
@@ -393,7 +394,7 @@ AVExpr *ff_parse_expr(const char *s,
     p.func1_name = func1_name;
     p.func2      = func2;
     p.func2_name = func2_name;
-    p.error= error;
+    p.log_ctx    = log_ctx;
 
     e = parse_expr(&p);
     if (!verify_expr(e)) {
@@ -417,8 +418,9 @@ double ff_parse_and_eval_expr(const char *s,
                               const char * const *const_name, const double *const_value,
                               const char * const *func1_name, double (* const *func1)(void *, double),
                               const char * const *func2_name, double (* const *func2)(void *, double, double),
-               void *opaque, const char **error){
-    AVExpr *e = ff_parse_expr(s, const_name, func1_name, func1, func2_name, func2, error);
+                              void *opaque, void *log_ctx)
+{
+    AVExpr *e = ff_parse_expr(s, const_name, func1_name, func1, func2_name, func2, log_ctx);
     double d;
     if (!e) return NAN;
     d = ff_eval_expr(e, const_value, opaque);
diff --git a/libavcodec/eval.h b/libavcodec/eval.h
index 0803397..fbf0437 100644
--- a/libavcodec/eval.h
+++ b/libavcodec/eval.h
@@ -40,14 +40,14 @@ typedef struct AVExpr AVExpr;
  * @param func2_name NULL terminated array of zero terminated strings of func2 identifers
  * @param func2 NULL terminated array of function pointers for functions which take 2 arguments
  * @param opaque a pointer which will be passed to all functions from func1 and func2
- * @param error pointer to a char* which is set to an error message if something goes wrong
+ * @param log_ctx logging context
  * @return the value of the expression
  */
 double ff_parse_and_eval_expr(const char *s,
                               const char * const *const_name, const double *const_value,
                               const char * const *func1_name, double (* const *func1)(void *, double),
                               const char * const *func2_name, double (* const *func2)(void *, double, double),
-               void *opaque, const char **error);
+                              void *opaque, void *log_ctx);
 
 /**
  * Parses an expression.
@@ -58,7 +58,7 @@ double ff_parse_and_eval_expr(const char *s,
  * @param func1 NULL terminated array of function pointers for functions which take 1 argument
  * @param func2_name NULL terminated array of zero terminated strings of func2 identifers
  * @param func2 NULL terminated array of function pointers for functions which take 2 arguments
- * @param error pointer to a char* which is set to an error message if something goes wrong
+ * @param log_ctx logging context
  * @return AVExpr which must be freed with ff_free_expr() by the user when it is not needed anymore
  *         NULL if anything went wrong
  */
@@ -66,7 +66,7 @@ AVExpr *ff_parse_expr(const char *s,
                       const char * const *const_name,
                       const char * const *func1_name, double (* const *func1)(void *, double),
                       const char * const *func2_name, double (* const *func2)(void *, double, double),
-               const char **error);
+                      void *log_ctx);
 
 /**
  * Evaluates a previously parsed expression.
diff --git a/libavcodec/opt.c b/libavcodec/opt.c
index f9cba05..844c0ec 100644
--- a/libavcodec/opt.c
+++ b/libavcodec/opt.c
@@ -147,7 +147,6 @@ int av_set_string3(void *obj, const char *name, const char *val, int alloc, cons
             char buf[256];
             int cmd=0;
             double d;
-            const char *error = NULL;
 
             if(*val == '+' || *val == '-')
                 cmd= *(val++);
@@ -156,7 +155,9 @@ int av_set_string3(void *obj, const char *name, const char *val, int alloc, cons
                 buf[i]= val[i];
             buf[i]=0;
 
-            d = ff_parse_and_eval_expr(buf, const_values, const_names, NULL, NULL, NULL, NULL, NULL, &error);
+            av_set_int(obj, "log_level_offset", AV_LOG_DEBUG - AV_LOG_QUIET);
+            d = ff_parse_and_eval_expr(buf, const_names, const_values, NULL, NULL, NULL, NULL, NULL, obj);
+            av_set_int(obj, "log_level_offset", 0);
             if(isnan(d)) {
                 const AVOption *o_named= av_find_opt(obj, buf, o->unit, 0, 0);
                 if(o_named && o_named->type == FF_OPT_TYPE_CONST)
@@ -167,8 +168,7 @@ int av_set_string3(void *obj, const char *name, const char *val, int alloc, cons
                 else if(!strcmp(buf, "none"   )) d= 0;
                 else if(!strcmp(buf, "all"    )) d= ~0;
                 else {
-                    if (error)
-                        av_log(obj, AV_LOG_ERROR, "Unable to parse option value \"%s\": %s\n", val, error);
+                    av_log(obj, AV_LOG_ERROR, "Unable to parse or evaluate option value \"%s\"\n", val);
                     return AVERROR(EINVAL);
                 }
             }
diff --git a/libavcodec/ratecontrol.c b/libavcodec/ratecontrol.c
index 1c459d8..fa5dad2 100644
--- a/libavcodec/ratecontrol.c
+++ b/libavcodec/ratecontrol.c
@@ -31,6 +31,7 @@
 #include "ratecontrol.h"
 #include "mpegvideo.h"
 #include "eval.h"
+#include "opt.h"
 
 #undef NDEBUG // Always check asserts, the speed effect is far too small to disable them.
 #include <assert.h>
@@ -67,7 +68,6 @@ int ff_rate_control_init(MpegEncContext *s)
 {
     RateControlContext *rcc= &s->rc_context;
     int i;
-    const char *error = NULL;
     static const char * const const_names[]={
         "PI",
         "E",
@@ -107,9 +107,9 @@ int ff_rate_control_init(MpegEncContext *s)
     };
     emms_c();
 
-    rcc->rc_eq_eval = ff_parse_expr(s->avctx->rc_eq ? s->avctx->rc_eq : "tex^qComp", const_names, func1_names, func1, NULL, NULL, &error);
+    rcc->rc_eq_eval = ff_parse_expr(s->avctx->rc_eq ? s->avctx->rc_eq : "tex^qComp", const_names, func1_names, func1, NULL, NULL, s->avctx);
     if (!rcc->rc_eq_eval) {
-        av_log(s->avctx, AV_LOG_ERROR, "Error parsing rc_eq \"%s\": %s\n", s->avctx->rc_eq, error? error : "");
+        av_log(s->avctx, AV_LOG_ERROR, "Error parsing rc_eq \"%s\"\n", s->avctx->rc_eq);
         return -1;
     }
 
-- 
1.7.0


--/9DWx/yDrRhgMJTb--



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