iLBC: Some const annotations

NOTRY=true
BUG=chromium:617124

Review-Url: https://codereview.webrtc.org/2293843002
Cr-Commit-Position: refs/heads/master@{#13972}

webrtc/modules/audio_coding/codecs/ilbc/cb_construct.c

@@ -28,12 +28,11 @@
 
 bool WebRtcIlbcfix_CbConstruct(
     int16_t* decvector,        /* (o) Decoded vector */
-    int16_t *index,   /* (i) Codebook indices */
+    const int16_t* index,      /* (i) Codebook indices */
-    int16_t *gain_index,  /* (i) Gain quantization indices */
+    const int16_t* gain_index, /* (i) Gain quantization indices */
     int16_t* mem,              /* (i) Buffer for codevector construction */
     size_t lMem,               /* (i) Length of buffer */
-    size_t veclen   /* (i) Length of vector */
+    size_t veclen) {           /* (i) Length of vector */
-                               ){
   size_t j;
   int16_t gain[CB_NSTAGES];
   /* Stack based */

webrtc/modules/audio_coding/codecs/ilbc/cb_construct.h

@@ -29,8 +29,8 @@
 // Returns true on success, false on failure.
 bool WebRtcIlbcfix_CbConstruct(
     int16_t* decvector,        /* (o) Decoded vector */
-    int16_t* index,      /* (i) Codebook indices */
+    const int16_t* index,      /* (i) Codebook indices */
-    int16_t* gain_index, /* (i) Gain quantization indices */
+    const int16_t* gain_index, /* (i) Gain quantization indices */
     int16_t* mem,              /* (i) Buffer for codevector construction */
     size_t lMem,               /* (i) Length of buffer */
     size_t veclen              /* (i) Length of vector */

webrtc/modules/audio_coding/codecs/ilbc/create_augmented_vec.c

@@ -26,13 +26,14 @@
  *----------------------------------------------------------------*/
 
 void WebRtcIlbcfix_CreateAugmentedVec(
-    size_t index,  /* (i) Index for the augmented vector to be created */
+    size_t index,          /* (i) Index for the augmented vector to be
-    int16_t *buffer,  /* (i) Pointer to the end of the codebook memory that
+                              created */
-                                           is used for creation of the augmented codebook */
+    const int16_t* buffer, /* (i) Pointer to the end of the codebook memory
-    int16_t *cbVec  /* (o) The constructed codebook vector */
+                              that is used for creation of the augmented
-                                      ) {
+                              codebook */
+    int16_t* cbVec) {      /* (o) The constructed codebook vector */
   size_t ilow;
-  int16_t *ppo, *ppi;
+  const int16_t *ppo, *ppi;
   int16_t cbVecTmp[4];
   /* Interpolation starts 4 elements before cbVec+index, but must not start
      outside |cbVec|; clamping interp_len to stay within |cbVec|.

webrtc/modules/audio_coding/codecs/ilbc/create_augmented_vec.h

@@ -27,10 +27,11 @@
  *----------------------------------------------------------------*/
 
 void WebRtcIlbcfix_CreateAugmentedVec(
-    size_t index,  /* (i) Index for the augmented vector to be created */
+    size_t index,          /* (i) Index for the augmented vector to be
-    int16_t *buffer,  /* (i) Pointer to the end of the codebook memory that
+                              created */
-                                           is used for creation of the augmented codebook */
+    const int16_t* buffer, /* (i) Pointer to the end of the codebook memory
-    int16_t *cbVec  /* (o) The construced codebook vector */
+                              that is used for creation of the augmented
-                                      );
+                              codebook */
+    int16_t* cbVec);       /* (o) The construced codebook vector */
 
 #endif