modified error system, following suggestions by @nemequ

lib/bitstream.h

@@ -51,7 +51,7 @@ extern "C" {
 *  Includes
 ******************************************/
 #include "mem.h"            /* unaligned access routines */
-#include "error.h"   /* error codes and messages */
+#include "error_private.h"  /* error codes and messages */
 
 
 /********************************************

lib/error_private.h

@@ -1,6 +1,6 @@
 /* ******************************************************************
    Error codes and messages
-   Copyright (C) 2013-2015, Yann Collet
+   Copyright (C) 2013-2016, Yann Collet
 
    BSD 2-Clause License (http://www.opensource.org/licenses/bsd-license.php)
 
@@ -28,9 +28,10 @@
    OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
    You can contact the author at :
-   - Source repository : https://github.com/Cyan4973/FiniteStateEntropy
+   - Source repository : https://github.com/Cyan4973/zstd
-   - Public forum : https://groups.google.com/forum/#!forum/lz4c
 ****************************************************************** */
+/* Note : this module is expected to remain private, do not expose it */
+
 #ifndef ERROR_H_MODULE
 #define ERROR_H_MODULE
 
@@ -43,24 +44,25 @@ extern "C" {
 *  Includes
 ******************************************/
 #include <stddef.h>        /* size_t, ptrdiff_t */
+#include "error_public.h"  /* enum list */
 
 
 /* *****************************************
 *  Compiler-specific
 ******************************************/
-#if defined (__cplusplus) || (defined (__STDC_VERSION__) && (__STDC_VERSION__ >= 199901L) /* C99 */)
+#if defined(__GNUC__)
+#  define ERR_STATIC static __attribute__((unused))
+#elif defined (__cplusplus) || (defined (__STDC_VERSION__) && (__STDC_VERSION__ >= 199901L) /* C99 */)
 #  define ERR_STATIC static inline
 #elif defined(_MSC_VER)
 #  define ERR_STATIC static __inline
-#elif defined(__GNUC__)
-#  define ERR_STATIC static __attribute__((unused))
 #else
 #  define ERR_STATIC static  /* this version may generate warnings for unused static functions; disable the relevant warning */
 #endif
 
 
 /* *****************************************
-*  Error Management
+*  Error Codes
 ******************************************/
 #define PREFIX(name) ZSTD_error_##name
 
@@ -69,29 +71,34 @@ extern "C" {
 #endif
 #define ERROR(name) (size_t)-PREFIX(name)
 
-#define ERROR_LIST(ITEM) \
-        ITEM(PREFIX(No_Error)) ITEM(PREFIX(GENERIC)) \
-        ITEM(PREFIX(prefix_unknown)) ITEM(PREFIX(frameParameter_unsupported)) ITEM(PREFIX(frameParameter_unsupportedBy32bitsImplementation)) \
-        ITEM(PREFIX(init_missing)) ITEM(PREFIX(memory_allocation)) ITEM(PREFIX(stage_wrong)) \
-        ITEM(PREFIX(dstSize_tooSmall)) ITEM(PREFIX(srcSize_wrong)) \
-        ITEM(PREFIX(corruption_detected)) \
-        ITEM(PREFIX(tableLog_tooLarge)) ITEM(PREFIX(maxSymbolValue_tooLarge)) ITEM(PREFIX(maxSymbolValue_tooSmall)) \
-        ITEM(PREFIX(maxCode))
-
-#define ERROR_GENERATE_ENUM(ENUM) ENUM,
-typedef enum { ERROR_LIST(ERROR_GENERATE_ENUM) } ERR_codes;  /* enum is exposed, to detect & handle specific errors; compare function result to -enum value */
-
-#define ERROR_CONVERTTOSTRING(STRING) #STRING,
-#define ERROR_GENERATE_STRING(EXPR) ERROR_CONVERTTOSTRING(EXPR)
-static const char* ERR_strings[] = { ERROR_LIST(ERROR_GENERATE_STRING) };
-
 ERR_STATIC unsigned ERR_isError(size_t code) { return (code > ERROR(maxCode)); }
 
+
+/* *****************************************
+*  Error Strings
+******************************************/
+
 ERR_STATIC const char* ERR_getErrorName(size_t code)
 {
     static const char* codeError = "Unspecified error code";
-    if (ERR_isError(code)) return ERR_strings[-(int)(code)];
+    switch( (size_t)-code )
-    return codeError;
+    {
+    case ZSTD_error_No_Error: return "No error detected";
+    case ZSTD_error_GENERIC:  return "Error (generic)";
+    case ZSTD_error_prefix_unknown: return "Unknown frame descriptor";
+    case ZSTD_error_frameParameter_unsupported: return "Unsupported frame parameter";
+    case ZSTD_error_frameParameter_unsupportedBy32bitsImplementation: return "Frame parameter unsupported in 32-bits mode";
+    case ZSTD_error_init_missing: return "Context should be init first";
+    case ZSTD_error_memory_allocation: return "Allocation error : not enough memory";
+    case ZSTD_error_dstSize_tooSmall: return "Destination buffer is too small";
+    case ZSTD_error_srcSize_wrong: return "Src size incorrect";
+    case ZSTD_error_corruption_detected: return "Corrupted block detected";
+    case ZSTD_error_tableLog_tooLarge: return "tableLog requires too much memory";
+    case ZSTD_error_maxSymbolValue_tooLarge: return "Unsupported max possible Symbol Value : too large";
+    case ZSTD_error_maxSymbolValue_tooSmall: return "Specified maxSymbolValue is too small";
+    case ZSTD_error_maxCode:
+    default: return codeError;
+    }
 }
 
 

lib/error_public.h

@@ -0,0 +1,69 @@
+/* ******************************************************************
+   Error codes list
+   Copyright (C) 2016, Yann Collet
+
+   BSD 2-Clause License (http://www.opensource.org/licenses/bsd-license.php)
+
+   Redistribution and use in source and binary forms, with or without
+   modification, are permitted provided that the following conditions are
+   met:
+
+       * Redistributions of source code must retain the above copyright
+   notice, this list of conditions and the following disclaimer.
+       * Redistributions in binary form must reproduce the above
+   copyright notice, this list of conditions and the following disclaimer
+   in the documentation and/or other materials provided with the
+   distribution.
+
+   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+   You can contact the author at :
+   - Source repository : https://github.com/Cyan4973/zstd
+****************************************************************** */
+#ifndef ERROR_PUBLIC_H_MODULE
+#define ERROR_PUBLIC_H_MODULE
+
+#if defined (__cplusplus)
+extern "C" {
+#endif
+
+
+/* ****************************************
+*  error list
+******************************************/
+enum {
+  ZSTD_error_No_Error,
+  ZSTD_error_GENERIC,
+  ZSTD_error_prefix_unknown,
+  ZSTD_error_frameParameter_unsupported,
+  ZSTD_error_frameParameter_unsupportedBy32bitsImplementation,
+  ZSTD_error_init_missing,
+  ZSTD_error_memory_allocation,
+  ZSTD_error_stage_wrong,
+  ZSTD_error_dstSize_tooSmall,
+  ZSTD_error_srcSize_wrong,
+  ZSTD_error_corruption_detected,
+  ZSTD_error_tableLog_tooLarge,
+  ZSTD_error_maxSymbolValue_tooLarge,
+  ZSTD_error_maxSymbolValue_tooSmall,
+  ZSTD_error_maxCode
+};
+
+/* note : functions provide error codes are provided as (size_t)-enum */
+
+
+#if defined (__cplusplus)
+}
+#endif
+
+#endif /* ERROR_PUBLIC_H_MODULE */

lib/zstd_buffered.c

@@ -39,7 +39,7 @@
 *  Includes
 ***************************************/
 #include <stdlib.h>
-#include "error.h"
+#include "error_private.h"
 #include "zstd_static.h"
 #include "zstd_buffered_static.h"
 
@@ -243,6 +243,8 @@ static size_t ZBUFF_compressContinue_generic(ZBUFF_CCtx* zbc,
                 zbc->stage = ZBUFFcs_load;
                 break;
             }
+        default:
+            return ERROR(GENERIC);   /* impossible */
         }
     }
 
@@ -534,6 +536,7 @@ size_t ZBUFF_decompressContinue(ZBUFF_DCtx* zbc, void* dst, size_t* maxDstSizePt
                 notDone = 0;
                 break;
             }
+        default: return ERROR(GENERIC);   /* impossible */
         }
     }
 

lib/zstd_internal.h

@@ -41,7 +41,7 @@ extern "C" {
 *  Includes
 ***************************************/
 #include "mem.h"
-#include "error.h"
+#include "error_private.h"
 
 
 /* *************************************

lib/zstd_static.h

@@ -334,7 +334,7 @@ static const ZSTD_parameters ZSTD_defaultParameters[4][ZSTD_MAX_CLEVEL+1] = {
 /* *************************************
 *  Error management
 ***************************************/
-#include "error.h"
+#include "error_public.h"
 
 
 #if defined (__cplusplus)

programs/Makefile

@@ -45,7 +45,7 @@ DESTDIR?=
 PREFIX ?= /usr/local
 CPPFLAGS= -I../lib -DZSTD_VERSION=\"$(VERSION)\"
 CFLAGS ?= -O3  # -falign-loops=32   # not always beneficial
-CFLAGS += -std=c99 -Wall -Wextra -Wundef -Wshadow -Wcast-qual -Wcast-align -Wstrict-prototypes -Wstrict-aliasing=1
+CFLAGS += -std=c99 -Wall -Wextra -Wcast-qual -Wcast-align -Wshadow -Wstrict-aliasing=1 -Wswitch-enum -Wstrict-prototypes -Wundef
 FLAGS   = $(CPPFLAGS) $(CFLAGS) $(LDFLAGS) $(MOREFLAGS)
 
 BINDIR  = $(PREFIX)/bin

programs/fuzzer.c

@@ -185,13 +185,13 @@ static int basicUnitTests(U32 seed, double compressibility)
     DISPLAYLEVEL(4, "test%3i : decompress with 1 missing byte : ", testNb++);
     result = ZSTD_decompress(decodedBuffer, COMPRESSIBLE_NOISE_LENGTH, compressedBuffer, cSize-1);
     if (!ZSTD_isError(result)) goto _output_error;
-    if (result != ERROR(srcSize_wrong)) goto _output_error;
+    if (result != (size_t)-ZSTD_error_srcSize_wrong) goto _output_error;
     DISPLAYLEVEL(4, "OK \n");
 
     DISPLAYLEVEL(4, "test%3i : decompress with 1 too much byte : ", testNb++);
     result = ZSTD_decompress(decodedBuffer, COMPRESSIBLE_NOISE_LENGTH, compressedBuffer, cSize+1);
     if (!ZSTD_isError(result)) goto _output_error;
-    if (result != ERROR(srcSize_wrong)) goto _output_error;
+    if (result != (size_t)-ZSTD_error_srcSize_wrong) goto _output_error;
     DISPLAYLEVEL(4, "OK \n");
 
     /* Dictionary and Duplication tests */
@@ -259,7 +259,7 @@ static int basicUnitTests(U32 seed, double compressibility)
     DISPLAYLEVEL(4, "test%3i : Check input length for magic number : ", testNb++);
     result = ZSTD_decompress(decodedBuffer, COMPRESSIBLE_NOISE_LENGTH, CNBuffer, 3);
     if (!ZSTD_isError(result)) goto _output_error;
-    if (result != ERROR(srcSize_wrong)) goto _output_error;
+    if (result != (size_t)-ZSTD_error_srcSize_wrong) goto _output_error;
     DISPLAYLEVEL(4, "OK \n");
 
     DISPLAYLEVEL(4, "test%3i : Check magic Number : ", testNb++);