pinned down error code enum values

Note : all error codes are changed by this new version,
but it's expected to be the last change for existing codes.

Codes are now grouped by category, and receive a manually attributed value.
The objective is to guarantee that
error code values will not change in the future
when introducing new codes.
Intentionnal empty spaces and ranges are defined
in order to keep room for potential new codes.

lib/compress/zstd_compress.c

@@ -214,7 +214,7 @@ size_t ZSTD_setCCtxParameter(ZSTD_CCtx* cctx, ZSTD_CCtxParameter param, unsigned
     ZSTD_STATIC_ASSERT(ZSTD_dm_auto==0);
     ZSTD_STATIC_ASSERT(ZSTD_dm_rawContent==1);
     case ZSTD_p_forceRawDict : cctx->dictMode = (ZSTD_dictMode_e)(value>0); return 0;
-    default: return ERROR(parameter_unknown);
+    default: return ERROR(parameter_unsupported);
     }
 }
 
@@ -228,9 +228,9 @@ static void ZSTD_cLevelToCParams(ZSTD_CCtx* cctx)
     cctx->compressionLevel = ZSTD_CLEVEL_CUSTOM;
 }
 
-#define CLAMPCHECK(val,min,max) {                       \
-    if (((val)<(min)) | ((val)>(max))) {                \
-        return ERROR(compressionParameter_outOfBound);  \
+#define CLAMPCHECK(val,min,max) {            \
+    if (((val)<(min)) | ((val)>(max))) {     \
+        return ERROR(parameter_outOfBound);  \
 }   }
 
 size_t ZSTD_CCtx_setParameter(ZSTD_CCtx* cctx, ZSTD_cParameter param, unsigned value)
@@ -326,7 +326,7 @@ size_t ZSTD_CCtx_setParameter(ZSTD_CCtx* cctx, ZSTD_cParameter param, unsigned v
         /* restrict dictionary mode, to "rawContent" or "fullDict" only */
         ZSTD_STATIC_ASSERT((U32)ZSTD_dm_fullDict > (U32)ZSTD_dm_rawContent);
         if (value > (unsigned)ZSTD_dm_fullDict)
-            return ERROR(compressionParameter_outOfBound);
+            return ERROR(parameter_outOfBound);
         cctx->dictMode = (ZSTD_dictMode_e)value;
         return 0;
 
@@ -347,11 +347,11 @@ size_t ZSTD_CCtx_setParameter(ZSTD_CCtx* cctx, ZSTD_cParameter param, unsigned v
         if (value==0) return 0;
         DEBUGLOG(5, " setting nbThreads : %u", value);
 #ifndef ZSTD_MULTITHREAD
-        if (value > 1) return ERROR(compressionParameter_unsupported);
+        if (value > 1) return ERROR(parameter_unsupported);
 #endif
         if ((value>1) && (cctx->nbThreads != value)) {
             if (cctx->staticSize)  /* MT not compatible with static alloc */
-                return ERROR(compressionParameter_unsupported);
+                return ERROR(parameter_unsupported);
             ZSTDMT_freeCCtx(cctx->mtctx);
             cctx->nbThreads = 1;
             cctx->mtctx = ZSTDMT_createCCtx_advanced(value, cctx->customMem);
@@ -361,17 +361,17 @@ size_t ZSTD_CCtx_setParameter(ZSTD_CCtx* cctx, ZSTD_cParameter param, unsigned v
         return 0;
 
     case ZSTD_p_jobSize:
-        if (cctx->nbThreads <= 1) return ERROR(compressionParameter_unsupported);
+        if (cctx->nbThreads <= 1) return ERROR(parameter_unsupported);
         assert(cctx->mtctx != NULL);
         return ZSTDMT_setMTCtxParameter(cctx->mtctx, ZSTDMT_p_sectionSize, value);
 
     case ZSTD_p_overlapSizeLog:
         DEBUGLOG(5, " setting overlap with nbThreads == %u", cctx->nbThreads);
-        if (cctx->nbThreads <= 1) return ERROR(compressionParameter_unsupported);
+        if (cctx->nbThreads <= 1) return ERROR(parameter_unsupported);
         assert(cctx->mtctx != NULL);
         return ZSTDMT_setMTCtxParameter(cctx->mtctx, ZSTDMT_p_overlapSectionLog, value);
 
-    default: return ERROR(parameter_unknown);
+    default: return ERROR(parameter_unsupported);
     }
 }
 
@@ -451,7 +451,8 @@ size_t ZSTD_checkCParams(ZSTD_compressionParameters cParams)
     CLAMPCHECK(cParams.searchLog, ZSTD_SEARCHLOG_MIN, ZSTD_SEARCHLOG_MAX);
     CLAMPCHECK(cParams.searchLength, ZSTD_SEARCHLENGTH_MIN, ZSTD_SEARCHLENGTH_MAX);
     CLAMPCHECK(cParams.targetLength, ZSTD_TARGETLENGTH_MIN, ZSTD_TARGETLENGTH_MAX);
-    if ((U32)(cParams.strategy) > (U32)ZSTD_btultra) return ERROR(compressionParameter_unsupported);
+    if ((U32)(cParams.strategy) > (U32)ZSTD_btultra)
+        return ERROR(parameter_unsupported);
     return 0;
 }
 

lib/compress/zstdmt_compress.c

@@ -496,7 +496,7 @@ size_t ZSTDMT_setMTCtxParameter(ZSTDMT_CCtx* mtctx, ZSDTMT_parameter parameter,
         mtctx->overlapLog = (value >= 9) ? 9 : value;
         return 0;
     default :
-        return ERROR(compressionParameter_unsupported);
+        return ERROR(parameter_unsupported);
     }
 }