math_approx: use unsigned int for LCG pseudorandom generator

This avoids an integer overflow.

6 files changed, 9 insertions, 9 deletions

diff --git a/libspeex/cb_search.c b/libspeex/cb_search.c
index a170fd6..537d964 100644
--- a/libspeex/cb_search.c
+++ b/libspeex/cb_search.c
@@ -524,7 +524,7 @@ const void *par,                      /* non-overlapping codebook */
 int   nsf,                      /* number of samples in subframe */
 SpeexBits *bits,
 char *stack,
-spx_int32_t *seed
+spx_uint32_t *seed
 )
 {
    int i,j;
@@ -612,7 +612,7 @@ const void *par,                      /* non-overlapping codebook */
 int   nsf,                      /* number of samples in subframe */
 SpeexBits *bits,
 char *stack,
-spx_int32_t *seed
+spx_uint32_t *seed
 )
 {
    int i;
diff --git a/libspeex/cb_search.h b/libspeex/cb_search.h
index 50b530a..b9b4acc 100644
--- a/libspeex/cb_search.h
+++ b/libspeex/cb_search.h
@@ -70,7 +70,7 @@ const void *par,                /* non-overlapping codebook */
 int   nsf,                      /* number of samples in subframe */
 SpeexBits *bits,
 char *stack,
-spx_int32_t *seed
+spx_uint32_t *seed
 );
 
 
@@ -97,7 +97,7 @@ const void *par,                /* non-overlapping codebook */
 int   nsf,                      /* number of samples in subframe */
 SpeexBits *bits,
 char *stack,
-spx_int32_t *seed
+spx_uint32_t *seed
 );
 
 #endif
diff --git a/libspeex/math_approx.h b/libspeex/math_approx.h
index 9ca8307..6573113 100644
--- a/libspeex/math_approx.h
+++ b/libspeex/math_approx.h
@@ -46,7 +46,7 @@
 #define spx_atan atan
 
 /** Generate a pseudo-random number */
-static inline spx_word16_t speex_rand(spx_word16_t std, spx_int32_t *seed)
+static inline spx_word16_t speex_rand(spx_word16_t std, spx_uint32_t *seed)
 {
    const unsigned int jflone = 0x3f800000;
    const unsigned int jflmsk = 0x007fffff;
@@ -119,7 +119,7 @@ static inline spx_int16_t spx_ilog4(spx_uint32_t x)
 #ifdef FIXED_POINT
 
 /** Generate a pseudo-random number */
-static inline spx_word16_t speex_rand(spx_word16_t std, spx_int32_t *seed)
+static inline spx_word16_t speex_rand(spx_word16_t std, spx_uint32_t *seed)
 {
    spx_word32_t res;
    *seed = 1664525 * *seed + 1013904223;
diff --git a/libspeex/modes.h b/libspeex/modes.h
index 0977a57..cc8cad7 100644
--- a/libspeex/modes.h
+++ b/libspeex/modes.h
@@ -85,7 +85,7 @@ typedef void (*innovation_quant_func)(spx_word16_t *, spx_coef_t *, spx_coef_t *
                                       spx_sig_t *, spx_word16_t *, SpeexBits *, char *, int, int);
 
 /** Innovation unquantization function */
-typedef void (*innovation_unquant_func)(spx_sig_t *, const void *, int, SpeexBits*, char *, spx_int32_t *);
+typedef void (*innovation_unquant_func)(spx_sig_t *, const void *, int, SpeexBits*, char *, spx_uint32_t *);
 
 /** Description of a Speex sub-mode (wither narrowband or wideband */
 typedef struct SpeexSubmode {
diff --git a/libspeex/nb_celp.h b/libspeex/nb_celp.h
index a8d3088..1d2f205 100644
--- a/libspeex/nb_celp.h
+++ b/libspeex/nb_celp.h
@@ -149,7 +149,7 @@ typedef struct DecState {
    spx_word16_t  last_pitch_gain; /**< Pitch gain of last correctly decoded frame */
    spx_word16_t  pitch_gain_buf[3]; /**< Pitch gain of last decoded frames */
    int    pitch_gain_buf_idx;   /**< Tail of the buffer */
-   spx_int32_t seed;            /** Seed used for random number generation */
+   spx_uint32_t seed;            /** Seed used for random number generation */
    
    int    encode_submode;
    const SpeexSubmode * const *submodes; /**< Sub-mode data */
diff --git a/libspeex/sb_celp.h b/libspeex/sb_celp.h
index 141d0c2..0474d82 100644
--- a/libspeex/sb_celp.h
+++ b/libspeex/sb_celp.h
@@ -120,7 +120,7 @@ typedef struct SBDecState {
    spx_word16_t *innov_save;      /** If non-NULL, innovation is copied here */
    
    spx_word16_t last_ener;
-   spx_int32_t seed;
+   spx_uint32_t seed;
 
    int    encode_submode;
    const SpeexSubmode * const *submodes;