From a33bf89c62b1573a604144adaa797d94d97cb990 Mon Sep 17 00:00:00 2001

From: Yann Collet <cyan@fb.com>

Date: Wed, 15 Mar 2017 17:20:22 -0700

Subject: [PATCH] fix #332 : do not modify /dev/null permissions

---

 NEWS             |  4 +++

 programs/lz4io.c | 68 ++++++++++++++++++++++--------------------------

 programs/util.h  | 10 +++----

 3 files changed, 40 insertions(+), 42 deletions(-)

diff --git a/programs/lz4io.c b/programs/lz4io.c

index 5264b148..5bf54744 100644

--- a/programs/lz4io.c

+++ b/programs/lz4io.c

@@ -222,7 +222,7 @@ static int LZ4IO_isSkippableMagicNumber(unsigned int magic) { return (magic & LZ

 /** LZ4IO_openSrcFile() :

- * condition : `dstFileName` must be non-NULL.

+ * condition : `srcFileName` must be non-NULL.

  * @result : FILE* to `dstFileName`, or NULL if it fails */

 static FILE* LZ4IO_openSrcFile(const char* srcFileName)

 {

@@ -291,7 +291,7 @@ static FILE* LZ4IO_openDstFile(const char* dstFileName)

 /* unoptimized version; solves endianess & alignment issues */

 static void LZ4IO_writeLE32 (void* p, unsigned value32)

 {

-    unsigned char* dstPtr = (unsigned char*)p;

+    unsigned char* const dstPtr = (unsigned char*)p;

     dstPtr[0] = (unsigned char)value32;

     dstPtr[1] = (unsigned char)(value32 >> 8);

     dstPtr[2] = (unsigned char)(value32 >> 16);

@@ -317,10 +317,10 @@ int LZ4IO_compressFilename_Legacy(const char* input_filename, const char* output

     const int outBuffSize = LZ4_compressBound(LEGACY_BLOCKSIZE);

     FILE* finput;

     FILE* foutput;

-    clock_t end;

+    clock_t clockEnd;

     /* Init */

-    clock_t const start = clock();

+    clock_t const clockStart = clock();

     if (compressionlevel < 3) compressionFunction = LZ4IO_LZ4_compress; else compressionFunction = LZ4_compress_HC;

     finput = LZ4IO_openSrcFile(input_filename);

@@ -336,7 +336,7 @@ int LZ4IO_compressFilename_Legacy(const char* input_filename, const char* output

     /* Write Archive Header */

     LZ4IO_writeLE32(out_buff, LEGACY_MAGICNUMBER);

     { size_t const sizeCheck = fwrite(out_buff, 1, MAGICNUMBER_SIZE, foutput);

-      if (sizeCheck!=MAGICNUMBER_SIZE) EXM_THROW(22, "Write error : cannot write header"); }

+      if (sizeCheck != MAGICNUMBER_SIZE) EXM_THROW(22, "Write error : cannot write header"); }

     /* Main Loop */

     while (1) {

@@ -360,13 +360,13 @@ int LZ4IO_compressFilename_Legacy(const char* input_filename, const char* output

     if (ferror(finput)) EXM_THROW(25, "Error while reading %s ", input_filename);

     /* Status */

-    end = clock();

-    if (end==start) end+=1;  /* avoid division by zero (speed) */

+    clockEnd = clock();

+    if (clockEnd==clockStart) clockEnd+=1;  /* avoid division by zero (speed) */

     filesize += !filesize;   /* avoid division by zero (ratio) */

     DISPLAYLEVEL(2, "\r%79s\r", "");   /* blank line */

     DISPLAYLEVEL(2,"Compressed %llu bytes into %llu bytes ==> %.2f%%\n",

         filesize, compressedfilesize, (double)compressedfilesize / filesize * 100);

-    {   double const seconds = (double)(end - start) / CLOCKS_PER_SEC;

+    {   double const seconds = (double)(clockEnd - clockStart) / CLOCKS_PER_SEC;

         DISPLAYLEVEL(4,"Done in %.2f s ==> %.2f MB/s\n", seconds, (double)filesize / seconds / 1024 / 1024);

     }

@@ -603,11 +603,11 @@ static unsigned LZ4IO_readLE32 (const void* s)

     return value32;

 }

-#define sizeT sizeof(size_t)

-#define maskT (sizeT - 1)

 static unsigned LZ4IO_fwriteSparse(FILE* file, const void* buffer, size_t bufferSize, unsigned storedSkips)

 {

+    const size_t sizeT = sizeof(size_t);

+    const size_t maskT = sizeT -1 ;

     const size_t* const bufferT = (const size_t*)buffer;   /* Buffer is supposed malloc'ed, hence aligned on size_t */

     const size_t* ptrT = bufferT;

     size_t bufferSizeT = bufferSize / sizeT;

@@ -682,22 +682,19 @@ static void LZ4IO_fwriteSparseEnd(FILE* file, unsigned storedSkips)

 }

-static unsigned g_magicRead = 0;

+static unsigned g_magicRead = 0;   /* out-parameter of LZ4IO_decodeLegacyStream() */

 static unsigned long long LZ4IO_decodeLegacyStream(FILE* finput, FILE* foutput)

 {

-    unsigned long long filesize = 0;

-    char* in_buff;

-    char* out_buff;

+    unsigned long long streamSize = 0;

     unsigned storedSkips = 0;

     /* Allocate Memory */

-    in_buff = (char*)malloc(LZ4_compressBound(LEGACY_BLOCKSIZE));

-    out_buff = (char*)malloc(LEGACY_BLOCKSIZE);

+    char* const in_buff  = (char*)malloc(LZ4_compressBound(LEGACY_BLOCKSIZE));

+    char* const out_buff = (char*)malloc(LEGACY_BLOCKSIZE);

     if (!in_buff || !out_buff) EXM_THROW(51, "Allocation error : not enough memory");

     /* Main Loop */

     while (1) {

-        int decodeSize;

         unsigned int blockSize;

         /* Block Size */

@@ -716,13 +713,12 @@ static unsigned long long LZ4IO_decodeLegacyStream(FILE* finput, FILE* foutput)

           if (sizeCheck!=blockSize) EXM_THROW(52, "Read error : cannot access compressed block !"); }

         /* Decode Block */

-        decodeSize = LZ4_decompress_safe(in_buff, out_buff, blockSize, LEGACY_BLOCKSIZE);

-        if (decodeSize < 0) EXM_THROW(53, "Decoding Failed ! Corrupted input detected !");

-        filesize += decodeSize;

-

-        /* Write Block */

-        storedSkips = LZ4IO_fwriteSparse(foutput, out_buff, decodeSize, storedSkips);

-    }

+        {   int const decodeSize = LZ4_decompress_safe(in_buff, out_buff, blockSize, LEGACY_BLOCKSIZE);

+            if (decodeSize < 0) EXM_THROW(53, "Decoding Failed ! Corrupted input detected !");

+            streamSize += decodeSize;

+            /* Write Block */

+            storedSkips = LZ4IO_fwriteSparse(foutput, out_buff, decodeSize, storedSkips); /* success or die */

+    }   }

     if (ferror(finput)) EXM_THROW(54, "Read error : ferror");

     LZ4IO_fwriteSparseEnd(foutput, storedSkips);

@@ -731,7 +727,7 @@ static unsigned long long LZ4IO_decodeLegacyStream(FILE* finput, FILE* foutput)

     free(in_buff);

     free(out_buff);

-    return filesize;

+    return streamSize;

 }

@@ -925,10 +921,9 @@ static int LZ4IO_decompressSrcFile(dRess_t ress, const char* input_filename, con

 {

     FILE* const foutput = ress.dstFile;

     unsigned long long filesize = 0, decodedSize=0;

-    FILE* finput;

     /* Init */

-    finput = LZ4IO_openSrcFile(input_filename);

+    FILE* const finput = LZ4IO_openSrcFile(input_filename);

     if (finput==NULL) return 1;

     /* Loop over multiple streams */

@@ -954,10 +949,7 @@ static int LZ4IO_decompressSrcFile(dRess_t ress, const char* input_filename, con

 static int LZ4IO_decompressDstFile(dRess_t ress, const char* input_filename, const char* output_filename)

 {

-    FILE* foutput;

-

-    /* Init */

-    foutput = LZ4IO_openDstFile(output_filename);

+    FILE* const foutput = LZ4IO_openDstFile(output_filename);   /* success or die */

     if (foutput==NULL) return 1;   /* failure */

     ress.dstFile = foutput;

@@ -967,8 +959,11 @@ static int LZ4IO_decompressDstFile(dRess_t ress, const char* input_filename, con

     /* Copy owner, file permissions and modification time */

     {   stat_t statbuf;

-        if (strcmp (input_filename, stdinmark) && strcmp (output_filename, stdoutmark) && UTIL_getFileStat(input_filename, &statbuf))

-            UTIL_setFileStat(output_filename, &statbuf);

+        if (strcmp (input_filename, stdinmark)

+            && strcmp (output_filename, stdoutmark)

+            && strcmp (output_filename, nulmark)

+            && UTIL_getFileStat(input_filename, &statbuf))

+            UTIL_setFileStat(output_filename, &statbuf);  /* should return value be read ? or is silent fail good enough ? */

     }

     return 0;

@@ -982,10 +977,9 @@ int LZ4IO_decompressFilename(const char* input_filename, const char* output_file

     int const missingFiles = LZ4IO_decompressDstFile(ress, input_filename, output_filename);

-    {   clock_t const end = clock();

-        double const seconds = (double)(end - start) / CLOCKS_PER_SEC;

-        DISPLAYLEVEL(4, "Done in %.2f sec  \n", seconds);

-    }

+    clock_t const end = clock();

+    double const seconds = (double)(end - start) / CLOCKS_PER_SEC;

+    DISPLAYLEVEL(4, "Done in %.2f sec  \n", seconds);

     LZ4IO_freeDResources(ress);

     return missingFiles;

diff --git a/programs/util.h b/programs/util.h

index 044085f3..5a69c55c 100644

--- a/programs/util.h

+++ b/programs/util.h

@@ -199,9 +199,9 @@ UTIL_STATIC int UTIL_setFileStat(const char *filename, stat_t *statbuf)

     int res = 0;

     struct utimbuf timebuf;

-	timebuf.actime = time(NULL);

-	timebuf.modtime = statbuf->st_mtime;

-	res += utime(filename, &timebuf);  /* set access and modification times */

+    timebuf.actime = time(NULL);

+    timebuf.modtime = statbuf->st_mtime;

+    res += utime(filename, &timebuf);  /* set access and modification times */

 #if !defined(_WIN32)

     res += chown(filename, statbuf->st_uid, statbuf->st_gid);  /* Copy ownership */