From: Yann Collet <cyan@fb.com>
Date: Tue, 2 Mar 2021 23:24:30 +0000 (-0800)
Subject: fixed const guarantees
X-Git-Tag: v1.4.10~28^2~8
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=c7e42e147b422366f266ec32a9b9e325293b02ce;p=thirdparty%2Fzstd.git

fixed const guarantees

read-only objects are properly const-ified in parameters
---

diff --git a/contrib/seekable_format/zstd_seekable.h b/contrib/seekable_format/zstd_seekable.h
index c02f097c4..bf0118a34 100644
--- a/contrib/seekable_format/zstd_seekable.h
+++ b/contrib/seekable_format/zstd_seekable.h
@@ -108,6 +108,7 @@ ZSTDLIB_API size_t ZSTD_seekable_freeFrameLog(ZSTD_frameLog* fl);
 ZSTDLIB_API size_t ZSTD_seekable_logFrame(ZSTD_frameLog* fl, unsigned compressedSize, unsigned decompressedSize, unsigned checksum);
 ZSTDLIB_API size_t ZSTD_seekable_writeSeekTable(ZSTD_frameLog* fl, ZSTD_outBuffer* output);
 
+
 /*-****************************************************************************
 *  Seekable decompression - HowTo
 *  A ZSTD_seekable object is required to tracking the seekTable.
@@ -155,10 +156,6 @@ ZSTDLIB_API size_t ZSTD_seekable_writeSeekTable(ZSTD_frameLog* fl, ZSTD_outBuffe
 ZSTDLIB_API ZSTD_seekable* ZSTD_seekable_create(void);
 ZSTDLIB_API size_t ZSTD_seekable_free(ZSTD_seekable* zs);
 
-/*===== Independent seek table management =====*/
-ZSTDLIB_API size_t ZSTD_seekable_copySeekTable(ZSTD_seekable* zs, ZSTD_seekTable** out);
-ZSTDLIB_API size_t ZSTD_seekTable_free(ZSTD_seekTable* st);
-
 /*===== Seekable decompression functions =====*/
 ZSTDLIB_API size_t ZSTD_seekable_initBuff(ZSTD_seekable* zs, const void* src, size_t srcSize);
 ZSTDLIB_API size_t ZSTD_seekable_initFile(ZSTD_seekable* zs, FILE* src);
@@ -167,20 +164,26 @@ ZSTDLIB_API size_t ZSTD_seekable_decompressFrame(ZSTD_seekable* zs, void* dst, s
 
 #define ZSTD_SEEKABLE_FRAMEINDEX_TOOLARGE (0ULL-2)
 /*===== Seekable seek table access functions =====*/
-ZSTDLIB_API unsigned ZSTD_seekable_getNumFrames(ZSTD_seekable* const zs);
-ZSTDLIB_API unsigned long long ZSTD_seekable_getFrameCompressedOffset(ZSTD_seekable* const zs, unsigned frameIndex);
-ZSTDLIB_API unsigned long long ZSTD_seekable_getFrameDecompressedOffset(ZSTD_seekable* const zs, unsigned frameIndex);
-ZSTDLIB_API size_t ZSTD_seekable_getFrameCompressedSize(ZSTD_seekable* const zs, unsigned frameIndex);
-ZSTDLIB_API size_t ZSTD_seekable_getFrameDecompressedSize(ZSTD_seekable* const zs, unsigned frameIndex);
-ZSTDLIB_API unsigned ZSTD_seekable_offsetToFrameIndex(ZSTD_seekable* const zs, unsigned long long offset);
+ZSTDLIB_API unsigned ZSTD_seekable_getNumFrames(const ZSTD_seekable* zs);
+ZSTDLIB_API unsigned long long ZSTD_seekable_getFrameCompressedOffset(const ZSTD_seekable* zs, unsigned frameIndex);
+ZSTDLIB_API unsigned long long ZSTD_seekable_getFrameDecompressedOffset(const ZSTD_seekable* zs, unsigned frameIndex);
+ZSTDLIB_API size_t ZSTD_seekable_getFrameCompressedSize(const ZSTD_seekable* zs, unsigned frameIndex);
+ZSTDLIB_API size_t ZSTD_seekable_getFrameDecompressedSize(const ZSTD_seekable* zs, unsigned frameIndex);
+ZSTDLIB_API unsigned ZSTD_seekable_offsetToFrameIndex(const ZSTD_seekable* zs, unsigned long long offset);
+
+
+/*===== Independent seek table management =====*/
+ZSTDLIB_API size_t ZSTD_seekable_copySeekTable(ZSTD_seekable* zs, ZSTD_seekTable** out);
+ZSTDLIB_API size_t ZSTD_seekTable_free(ZSTD_seekTable* st);
 
 /*===== Direct seek table access functions =====*/
-ZSTDLIB_API unsigned ZSTD_seekTable_getNumFrames(ZSTD_seekTable* const st);
-ZSTDLIB_API unsigned long long ZSTD_seekTable_getFrameCompressedOffset(ZSTD_seekTable* const st, unsigned frameIndex);
-ZSTDLIB_API unsigned long long ZSTD_seekTable_getFrameDecompressedOffset(ZSTD_seekTable* const st, unsigned frameIndex);
-ZSTDLIB_API size_t ZSTD_seekTable_getFrameCompressedSize(ZSTD_seekTable* const st, unsigned frameIndex);
-ZSTDLIB_API size_t ZSTD_seekTable_getFrameDecompressedSize(ZSTD_seekTable* const st, unsigned frameIndex);
-ZSTDLIB_API unsigned ZSTD_seekTable_offsetToFrameIndex(ZSTD_seekTable* const st, unsigned long long offset);
+ZSTDLIB_API unsigned ZSTD_seekTable_getNumFrames(const ZSTD_seekTable* st);
+ZSTDLIB_API unsigned long long ZSTD_seekTable_getFrameCompressedOffset(const ZSTD_seekTable* st, unsigned frameIndex);
+ZSTDLIB_API unsigned long long ZSTD_seekTable_getFrameDecompressedOffset(const ZSTD_seekTable* st, unsigned frameIndex);
+ZSTDLIB_API size_t ZSTD_seekTable_getFrameCompressedSize(const ZSTD_seekTable* st, unsigned frameIndex);
+ZSTDLIB_API size_t ZSTD_seekTable_getFrameDecompressedSize(const ZSTD_seekTable* st, unsigned frameIndex);
+ZSTDLIB_API unsigned ZSTD_seekTable_offsetToFrameIndex(const ZSTD_seekTable* st, unsigned long long offset);
+
 
 /*===== Seekable advanced I/O API =====*/
 typedef int(ZSTD_seekable_read)(void* opaque, void* buffer, size_t n);
diff --git a/contrib/seekable_format/zstdseek_decompress.c b/contrib/seekable_format/zstdseek_decompress.c
index 749d6cd9f..5315e6c36 100644
--- a/contrib/seekable_format/zstdseek_decompress.c
+++ b/contrib/seekable_format/zstdseek_decompress.c
@@ -233,12 +233,12 @@ size_t ZSTD_seekTable_free(ZSTD_seekTable* st)
  *  Performs a binary search to find the last frame with a decompressed offset
  *  <= pos
  *  @return : the frame's index */
-unsigned ZSTD_seekable_offsetToFrameIndex(ZSTD_seekable* const zs, unsigned long long pos)
+unsigned ZSTD_seekable_offsetToFrameIndex(const ZSTD_seekable* zs, unsigned long long pos)
 {
     return ZSTD_seekTable_offsetToFrameIndex(&zs->seekTable, pos);
 }
 
-unsigned ZSTD_seekTable_offsetToFrameIndex(ZSTD_seekTable* const st, unsigned long long pos)
+unsigned ZSTD_seekTable_offsetToFrameIndex(const ZSTD_seekTable* st, unsigned long long pos)
 {
     U32 lo = 0;
     U32 hi = (U32)st->tableLen;
@@ -259,57 +259,57 @@ unsigned ZSTD_seekTable_offsetToFrameIndex(ZSTD_seekTable* const st, unsigned lo
     return lo;
 }
 
-unsigned ZSTD_seekable_getNumFrames(ZSTD_seekable* const zs)
+unsigned ZSTD_seekable_getNumFrames(const ZSTD_seekable* zs)
 {
     return ZSTD_seekTable_getNumFrames(&zs->seekTable);
 }
 
-unsigned ZSTD_seekTable_getNumFrames(ZSTD_seekTable* const st)
+unsigned ZSTD_seekTable_getNumFrames(const ZSTD_seekTable* st)
 {
     assert(st->tableLen <= UINT_MAX);
     return (unsigned)st->tableLen;
 }
 
-unsigned long long ZSTD_seekable_getFrameCompressedOffset(ZSTD_seekable* const zs, unsigned frameIndex)
+unsigned long long ZSTD_seekable_getFrameCompressedOffset(const ZSTD_seekable* zs, unsigned frameIndex)
 {
     return ZSTD_seekTable_getFrameCompressedOffset(&zs->seekTable, frameIndex);
 }
 
-unsigned long long ZSTD_seekTable_getFrameCompressedOffset(ZSTD_seekTable* const st, unsigned frameIndex)
+unsigned long long ZSTD_seekTable_getFrameCompressedOffset(const ZSTD_seekTable* st, unsigned frameIndex)
 {
     if (frameIndex >= st->tableLen) return ZSTD_SEEKABLE_FRAMEINDEX_TOOLARGE;
     return st->entries[frameIndex].cOffset;
 }
 
-unsigned long long ZSTD_seekable_getFrameDecompressedOffset(ZSTD_seekable* const zs, unsigned frameIndex)
+unsigned long long ZSTD_seekable_getFrameDecompressedOffset(const ZSTD_seekable* zs, unsigned frameIndex)
 {
     return ZSTD_seekTable_getFrameDecompressedOffset(&zs->seekTable, frameIndex);
 }
 
-unsigned long long ZSTD_seekTable_getFrameDecompressedOffset(ZSTD_seekTable* const st, unsigned frameIndex)
+unsigned long long ZSTD_seekTable_getFrameDecompressedOffset(const ZSTD_seekTable* st, unsigned frameIndex)
 {
     if (frameIndex >= st->tableLen) return ZSTD_SEEKABLE_FRAMEINDEX_TOOLARGE;
     return st->entries[frameIndex].dOffset;
 }
 
-size_t ZSTD_seekable_getFrameCompressedSize(ZSTD_seekable* const zs, unsigned frameIndex)
+size_t ZSTD_seekable_getFrameCompressedSize(const ZSTD_seekable* zs, unsigned frameIndex)
 {
     return ZSTD_seekTable_getFrameCompressedSize(&zs->seekTable, frameIndex);
 }
 
-size_t ZSTD_seekTable_getFrameCompressedSize(ZSTD_seekTable* const st, unsigned frameIndex)
+size_t ZSTD_seekTable_getFrameCompressedSize(const ZSTD_seekTable* st, unsigned frameIndex)
 {
     if (frameIndex >= st->tableLen) return ERROR(frameIndex_tooLarge);
     return st->entries[frameIndex + 1].cOffset -
            st->entries[frameIndex].cOffset;
 }
 
-size_t ZSTD_seekable_getFrameDecompressedSize(ZSTD_seekable* const zs, unsigned frameIndex)
+size_t ZSTD_seekable_getFrameDecompressedSize(const ZSTD_seekable* zs, unsigned frameIndex)
 {
     return ZSTD_seekTable_getFrameDecompressedSize(&zs->seekTable, frameIndex);
 }
 
-size_t ZSTD_seekTable_getFrameDecompressedSize(ZSTD_seekTable* const st, unsigned frameIndex)
+size_t ZSTD_seekTable_getFrameDecompressedSize(const ZSTD_seekTable* st, unsigned frameIndex)
 {
     if (frameIndex > st->tableLen) return ERROR(frameIndex_tooLarge);
     return st->entries[frameIndex + 1].dOffset -
@@ -513,7 +513,7 @@ size_t ZSTD_seekable_decompress(ZSTD_seekable* zs, void* dst, size_t len, unsign
                 zs->in.size = toRead;
                 zs->in.pos = 0;
             }
-        }
+        }  /* while (zs->decompressedOffset < offset + len) */
     } while (zs->decompressedOffset != offset + len);
 
     return len;
@@ -525,8 +525,7 @@ size_t ZSTD_seekable_decompressFrame(ZSTD_seekable* zs, void* dst, size_t dstSiz
         return ERROR(frameIndex_tooLarge);
     }
 
-    {
-        size_t const decompressedSize =
+    {   size_t const decompressedSize =
                 zs->seekTable.entries[frameIndex + 1].dOffset -
                 zs->seekTable.entries[frameIndex].dOffset;
         if (dstSize < decompressedSize) {