rtspenc: include os_support.h for system without HAVE_POLL_H

[ffmpeg] / libavutil / rational.h

diff --git a/libavutil/rational.h b/libavutil/rational.h
index 0f415edf94e77eb97f7a5b404d9f8596348f43a3..789e4aca2cc1b2270f5be2bdcb99e310f1fbcd01 100644 (file)
--- a/libavutil/rational.h
+++ b/libavutil/rational.h
@@ -20,7 +20,7 @@
  */
 
 /**
- * @file libavutil/rational.h
+ * @file
  * rational numbers
  * @author Michael Niedermayer <michaelni@gmx.at>
  */
@@ -29,7 +29,8 @@
 #define AVUTIL_RATIONAL_H
 
 #include <stdint.h>
-#include "common.h"
+#include <limits.h>
+#include "attributes.h"
 
 /**
  * rational number numerator/denominator
@@ -40,20 +41,23 @@ typedef struct AVRational{
 } AVRational;
 
 /**
- * Compares two rationals.
+ * Compare two rationals.
  * @param a first rational
  * @param b second rational
- * @return 0 if a==b, 1 if a>b and -1 if a<b
+ * @return 0 if a==b, 1 if a>b, -1 if a<b, and INT_MIN if one of the
+ * values is of the form 0/0
  */
 static inline int av_cmp_q(AVRational a, AVRational b){
     const int64_t tmp= a.num * (int64_t)b.den - b.num * (int64_t)a.den;
 
-    if(tmp) return (tmp>>63)|1;
-    else    return 0;
+    if(tmp) return ((tmp ^ a.den ^ b.den)>>63)|1;
+    else if(b.den && a.den) return 0;
+    else if(a.num && b.num) return (a.num>>31) - (b.num>>31);
+    else                    return INT_MIN;
 }
 
 /**
- * Converts rational to double.
+ * Convert rational to double.
  * @param a rational to convert
  * @return (double) a
  */
@@ -62,7 +66,7 @@ static inline double av_q2d(AVRational a){
 }
 
 /**
- * Reduces a fraction.
+ * Reduce a fraction.
  * This is useful for framerate calculations.
  * @param dst_num destination numerator
  * @param dst_den destination denominator
@@ -74,7 +78,7 @@ static inline double av_q2d(AVRational a){
 int av_reduce(int *dst_num, int *dst_den, int64_t num, int64_t den, int64_t max);
 
 /**
- * Multiplies two rationals.
+ * Multiply two rationals.
  * @param b first rational
  * @param c second rational
  * @return b*c
@@ -82,7 +86,7 @@ int av_reduce(int *dst_num, int *dst_den, int64_t num, int64_t den, int64_t max)
 AVRational av_mul_q(AVRational b, AVRational c) av_const;
 
 /**
- * Divides one rational by another.
+ * Divide one rational by another.
  * @param b first rational
  * @param c second rational
  * @return b/c
@@ -90,7 +94,7 @@ AVRational av_mul_q(AVRational b, AVRational c) av_const;
 AVRational av_div_q(AVRational b, AVRational c) av_const;
 
 /**
- * Adds two rationals.
+ * Add two rationals.
  * @param b first rational
  * @param c second rational
  * @return b+c
@@ -98,7 +102,7 @@ AVRational av_div_q(AVRational b, AVRational c) av_const;
 AVRational av_add_q(AVRational b, AVRational c) av_const;
 
 /**
- * Subtracts one rational from another.
+ * Subtract one rational from another.
  * @param b first rational
  * @param c second rational
  * @return b-c
@@ -106,7 +110,9 @@ AVRational av_add_q(AVRational b, AVRational c) av_const;
 AVRational av_sub_q(AVRational b, AVRational c) av_const;
 
 /**
- * Converts a double precision floating point number to a rational.
+ * Convert a double precision floating point number to a rational.
+ * inf is expressed as {1,0} or {-1,0} depending on the sign.
+ *
  * @param d double to convert
  * @param max the maximum allowed numerator and denominator
  * @return (AVRational) d
@@ -120,7 +126,7 @@ AVRational av_d2q(double d, int max) av_const;
 int av_nearer_q(AVRational q, AVRational q1, AVRational q2);
 
 /**
- * Finds the nearest value in q_list to q.
+ * Find the nearest value in q_list to q.
  * @param q_list an array of rationals terminated by {0, 0}
  * @return the index of the nearest value found in the array
  */