refuse to compress directories

fix #1211, reported by @imba-tjd

3 files changed, 53 insertions, 28 deletions

diff --git a/programs/lz4io.c b/programs/lz4io.c
index 8b70b91..09d906e 100644
--- a/programs/lz4io.c
+++ b/programs/lz4io.c
@@ -325,11 +325,16 @@ static FILE* LZ4IO_openSrcFile(const char* srcFileName)
         DISPLAYLEVEL(4,"Using stdin for input \n");
         f = stdin;
         SET_BINARY_MODE(stdin);
-    } else {
-        f = fopen(srcFileName, "rb");
-        if (f==NULL) DISPLAYLEVEL(1, "%s: %s \n", srcFileName, strerror(errno));
+        return f;
+    }
+
+    if (UTIL_isDir(srcFileName)) {
+        DISPLAYLEVEL(1, "lz4: %s is a directory -- ignored \n", srcFileName);
+        return NULL;
     }
 
+    f = fopen(srcFileName, "rb");
+    if (f==NULL) DISPLAYLEVEL(1, "%s: %s \n", srcFileName, strerror(errno));
     return f;
 }
 
@@ -337,7 +342,8 @@ static FILE* LZ4IO_openSrcFile(const char* srcFileName)
  *  prefs is writable, because sparseFileSupport might be updated.
  *  condition : `dstFileName` must be non-NULL.
  * @result : FILE* to `dstFileName`, or NULL if it fails */
-static FILE* LZ4IO_openDstFile(const char* dstFileName, const LZ4IO_prefs_t* const prefs)
+static FILE*
+LZ4IO_openDstFile(const char* dstFileName, const LZ4IO_prefs_t* const prefs)
 {
     FILE* f;
     assert(dstFileName != NULL);
@@ -563,11 +569,14 @@ static void* LZ4IO_createDict(size_t* dictSize, const char* const dictFilename)
     char*  dictBuf;
     FILE* dictFile;
 
-    if (!circularBuf) END_PROCESS(25, "Allocation error : not enough memory for circular buffer");
-    if (!dictFilename) END_PROCESS(26, "Dictionary error : no filename provided");
+    if (!dictFilename)
+        END_PROCESS(26, "Dictionary error : no filename provided");
+    if (!circularBuf)
+        END_PROCESS(25, "Allocation error : not enough memory for circular buffer");
 
     dictFile = LZ4IO_openSrcFile(dictFilename);
-    if (!dictFile) END_PROCESS(27, "Dictionary error : could not open dictionary file");
+    if (!dictFile)
+        END_PROCESS(27, "Dictionary error : could not open dictionary file");
 
     /* opportunistically seek to the part of the file we care about.
      * If this fails it's not a problem since we'll just read everything anyways. */
@@ -1311,7 +1320,8 @@ LZ4IO_decompressSrcFile(dRess_t ress,
 
 static int
 LZ4IO_decompressDstFile(dRess_t ress,
-                        const char* input_filename, const char* output_filename,
+                        const char* input_filename,
+                        const char* output_filename,
                         const LZ4IO_prefs_t* const prefs)
 {
     int result;
diff --git a/programs/util.h b/programs/util.h
index 3192ddc..f1d8a92 100644
--- a/programs/util.h
+++ b/programs/util.h
@@ -195,10 +195,7 @@ UTIL_STATIC void* UTIL_realloc(void* ptr, size_t size)
 /*-****************************************
 *  String functions
 ******************************************/
-/*
- * A modified version of realloc().
- * If UTIL_realloc() fails the original block is freed.
-*/
+/* supports a==NULL or b==NULL */
 UTIL_STATIC int UTIL_sameString(const char* a, const char* b)
 {
     assert(a!=NULL && b!=NULL);  /* unsupported scenario */
@@ -430,6 +427,21 @@ UTIL_STATIC int UTIL_isRegFile(const char* infilename)
     return UTIL_getFileStat(infilename, &statbuf); /* Only need to know whether it is a regular file */
 }
 
+UTIL_STATIC int UTIL_isDir(const char* infilename)
+{
+    stat_t statbuf;
+    int r;
+#if defined(_MSC_VER)
+    r = _stat64(infilename, &statbuf);
+    if (r) return 0;
+    return (statbuf.st_mode & S_IFDIR);
+#else
+    r = stat(infilename, &statbuf);
+    if (r) return 0;
+    return (S_ISDIR(statbuf.st_mode));
+#endif
+}
+
 
 UTIL_STATIC U32 UTIL_isDirectory(const char* infilename)
 {
diff --git a/tests/test-lz4-basic.sh b/tests/test-lz4-basic.sh
index 1767827..260d751 100755
--- a/tests/test-lz4-basic.sh
+++ b/tests/test-lz4-basic.sh
@@ -5,7 +5,7 @@ FPREFIX="tmp-tlb"
 set -e
 
 remove () {
-    rm $FPREFIX*
+    rm -rf $FPREFIX*
 }
 
 trap remove EXIT
@@ -27,42 +27,45 @@ datagen -g33M     | lz4 --no-frame-crc | lz4 -t
 datagen -g256MB   | lz4 -vqB4D | lz4 -t --no-crc
 echo "hello world" > $FPREFIX-hw
 lz4 --rm -f $FPREFIX-hw $FPREFIX-hw.lz4
-test ! -f $FPREFIX-hw                      # must fail (--rm)
+test ! -f $FPREFIX-hw                   # must fail (--rm)
 test   -f $FPREFIX-hw.lz4
 lz4cat $FPREFIX-hw.lz4 | grep "hello world"
 unlz4 --rm $FPREFIX-hw.lz4 $FPREFIX-hw
 test   -f $FPREFIX-hw
-test ! -f $FPREFIX-hw.lz4                  # must fail (--rm)
-test ! -f $FPREFIX-hw.lz4.lz4              # must fail (unlz4)
-lz4cat $FPREFIX-hw               # pass-through mode
+test ! -f $FPREFIX-hw.lz4               # must fail (--rm)
+test ! -f $FPREFIX-hw.lz4.lz4           # must fail (unlz4)
+lz4cat $FPREFIX-hw                      # pass-through mode
 test   -f $FPREFIX-hw
-test ! -f $FPREFIX-hw.lz4                  # must fail (lz4cat)
-lz4 $FPREFIX-hw $FPREFIX-hw.lz4          # creates $FPREFIX-hw.lz4
+test ! -f $FPREFIX-hw.lz4               # must fail (lz4cat)
+lz4 $FPREFIX-hw $FPREFIX-hw.lz4         # creates $FPREFIX-hw.lz4
 lz4cat < $FPREFIX-hw.lz4 > ${FPREFIX}3  # checks lz4cat works with stdin (#285)
 diff -q $FPREFIX-hw ${FPREFIX}3
 lz4cat < $FPREFIX-hw > ${FPREFIX}2      # checks lz4cat works in pass-through mode
 diff -q $FPREFIX-hw ${FPREFIX}2
 cp $FPREFIX-hw ./-d
-lz4 --rm -- -d -d.lz4               # compresses ./d into ./-d.lz4
+lz4 --rm -- -d -d.lz4                   # compresses ./d into ./-d.lz4
 test   -f ./-d.lz4
 test ! -f ./-d
 mv ./-d.lz4 ./-z
-lz4 -d --rm -- -z ${FPREFIX}4          # uncompresses ./-z into $FPREFIX4
+lz4 -d --rm -- -z ${FPREFIX}4           # uncompresses ./-z into $FPREFIX4
 test ! -f ./-z
 diff -q $FPREFIX-hw ${FPREFIX}4
-lz4 ${FPREFIX}2 ${FPREFIX}3 ${FPREFIX}4 && exit 1    # must fail: refuse to handle 3+ file names
-lz4 -f $FPREFIX-hw                   # create $FPREFIX-hw.lz4, for next tests
-lz4 --list $FPREFIX-hw.lz4           # test --list on valid single-frame file
-lz4 --list < $FPREFIX-hw.lz4         # test --list from stdin (file only)
+lz4 ${FPREFIX}2 ${FPREFIX}3 ${FPREFIX}4 && exit 1  # must fail: refuse to handle 3+ file names
+mkdir -p ${FPREFIX}-dir
+lz4 ${FPREFIX}-dir && exit 1          # must fail: refuse to compress directory
+test ! -f ${FPREFIX}-dir.lz4          # must not create artifact (#1211)
+lz4 -f $FPREFIX-hw                    # create $FPREFIX-hw.lz4, for next tests
+lz4 --list $FPREFIX-hw.lz4            # test --list on valid single-frame file
+lz4 --list < $FPREFIX-hw.lz4          # test --list from stdin (file only)
 cat $FPREFIX-hw >> $FPREFIX-hw.lz4
-lz4 -f $FPREFIX-hw.lz4 && exit 1             # uncompress valid frame followed by invalid data (must fail now)
-lz4 -BX $FPREFIX-hw -c -q | lz4 -tv  # test block checksum
+lz4 -f $FPREFIX-hw.lz4 && exit 1      # uncompress valid frame followed by invalid data (must fail now)
+lz4 -BX $FPREFIX-hw -c -q | lz4 -tv   # test block checksum
 # datagen -g20KB generates the same file every single time
 # cannot save output of datagen -g20KB as input file to lz4 because the following shell commands are run before datagen -g20KB
 test "$(datagen -g20KB | lz4 -c --fast | wc -c)" -lt "$(datagen -g20KB | lz4 -c --fast=9 | wc -c)" # -1 vs -9
 test "$(datagen -g20KB | lz4 -c -1 | wc -c)" -lt "$(datagen -g20KB| lz4 -c --fast=1 | wc -c)" # 1 vs -1
 test "$(datagen -g20KB | lz4 -c --fast=1 | wc -c)" -eq "$(datagen -g20KB| lz4 -c --fast| wc -c)" # checks default fast compression is -1
-lz4 -c --fast=0 $FPREFIX-dg20K && exit 1 # lz4 should fail when fast=0
+lz4 -c --fast=0 $FPREFIX-dg20K && exit 1  # lz4 should fail when fast=0
 lz4 -c --fast=-1 $FPREFIX-dg20K && exit 1 # lz4 should fail when fast=-1
 # High --fast values can result in out-of-bound dereferences #876
 datagen -g1M | lz4 -c --fast=999999999 > $FPREFIX-trash