Merge branch 'dev' into dubtlazy

contrib/meson/meson.build

@@ -39,9 +39,19 @@ libzstd_srcs = [
 libzstd_includes = [include_directories(common_dir, dictbuilder_dir, compress_dir, lib_dir)]
 
 legacy = get_option('legacy_support')
+if legacy == '0'
+    legacy = 'false'
+endif
 if legacy != 'false'
+    if legacy == 'true'
+        legacy = '1'
+    endif
+    #See ZSTD_LEGACY_SUPPORT of programs/README.md
     message('Enabling legacy support back to version 0.' + legacy)
     legacy_int = legacy.to_int()
+    if legacy_int > 7
+        legacy_int = 7
+    endif
     libzstd_cflags = ['-DZSTD_LEGACY_SUPPORT=' + legacy]
 
     legacy_dir = join_paths(lib_dir, 'legacy')
@@ -84,7 +94,9 @@ libzstd = library('zstd',
                   include_directories: libzstd_includes,
                   c_args: libzstd_cflags,
                   dependencies: libzstd_deps,
-                  install: true)
+                  install: true,
+                  soversion: '1',
+                 )
 
 programs_dir = join_paths('..', '..', 'programs')
 

contrib/meson/meson_options.txt

@@ -1,2 +1,3 @@
 option('multithread', type: 'boolean', value: false)
-option('legacy_support', type: 'string', value: '4')
+option('legacy_support', type: 'string', value: '4',
+    description: 'True or false, or 7 to 1 for v0.7+ to v0.1+.')

lib/README.md

@@ -2,16 +2,19 @@ Zstandard library files
 ================================
 
 The __lib__ directory is split into several sub-directories,
-in order to make it easier to select or exclude specific features.
+in order to make it easier to select or exclude features.
 
 
 #### Building
 
-`Makefile` script is provided, supporting the standard set of commands,
+`Makefile` script is provided, supporting all standard [Makefile conventions](https://www.gnu.org/prep/standards/html_node/Makefile-Conventions.html#Makefile-Conventions),
-directories, and variables (see https://www.gnu.org/prep/standards/html_node/Command-Variables.html).
+including commands variables, staged install, directory variables and standard targets.
 - `make` : generates both static and dynamic libraries
 - `make install` : install libraries in default system directories
 
+`libzstd` default scope includes compression, decompression, dictionary building,
+and decoding support for legacy formats >= v0.4.0.
+
 
 #### API
 
@@ -27,29 +30,37 @@ Optional advanced features are exposed via :
 - `ZSTD_STATIC_LINKING_ONLY` : if this macro is defined _before_ including `zstd.h`,
                           it unlocks access to advanced experimental API,
                           exposed in second part of `zstd.h`.
-                          These APIs shall ___never be used with dynamic library___ !
+                          These APIs are not "stable", their definition may change in the future.
-                          They are not "stable", their definition may change in the future.
+                          As a consequencem, it shall ___never be used with dynamic library___ !
                           Only static linking is allowed.
 
 
 #### Modular build
 
+It's possible to compile only a limited set of features.
+
 - Directory `lib/common` is always required, for all variants.
 - Compression source code lies in `lib/compress`
 - Decompression source code lies in `lib/decompress`
 - It's possible to include only `compress` or only `decompress`, they don't depend on each other.
 - `lib/dictBuilder` : makes it possible to generate dictionaries from a set of samples.
-    The API is exposed in `lib/dictBuilder/zdict.h`.
+        The API is exposed in `lib/dictBuilder/zdict.h`.
-    This module depends on both `lib/common` and `lib/compress` .
+        This module depends on both `lib/common` and `lib/compress` .
-- `lib/legacy` : source code to decompress older zstd formats, starting from `v0.1`.
+- `lib/legacy` : source code to decompress legacy zstd formats, starting from `v0.1.0`.
-              This module depends on `lib/common` and `lib/decompress`.
+        This module depends on `lib/common` and `lib/decompress`.
-              To enable this feature, it's necessary to define `ZSTD_LEGACY_SUPPORT = 1` during compilation.
+        To enable this feature, it's required to define `ZSTD_LEGACY_SUPPORT` during compilation.
-              Typically, with `gcc`, add argument `-DZSTD_LEGACY_SUPPORT=1`.
+        Typically, with `gcc`, add argument `-DZSTD_LEGACY_SUPPORT=1`.
-              Using higher number limits the number of version supported.
+        Using higher number limits versions supported.
-              For example, `ZSTD_LEGACY_SUPPORT=2` means : "support legacy formats starting from v0.2+".
+        For example, `ZSTD_LEGACY_SUPPORT=2` means : "support legacy formats >= v0.2.0".
-              The API is exposed in `lib/legacy/zstd_legacy.h`.
+        `ZSTD_LEGACY_SUPPORT=3` means : "support legacy formats >= v0.3.0", and so on.
-              Each version also provides a (dedicated) set of advanced API.
+        Starting v0.8.0, all versions of `zstd` produce frames compliant with specification.
-              For example, advanced API for version `v0.4` is exposed in `lib/legacy/zstd_v04.h` .
+        As a consequence, `ZSTD_LEGACY_SUPPORT=8` (or more) doesn't trigger legacy support.
+        Also, `ZSTD_LEGACY_SUPPORT=0` means "do __not__ support legacy formats".
+        Once enabled, this capability is transparently triggered within decompression functions.
+        It's also possible to invoke directly legacy API, as exposed in `lib/legacy/zstd_legacy.h`.
+        Each version also provides an additional dedicated set of advanced API.
+        For example, advanced API for version `v0.4` is exposed in `lib/legacy/zstd_v04.h` .
+        Note : `lib/legacy` only supports _decoding_ legacy formats.
 
 
 #### Multithreading support
@@ -57,19 +68,16 @@ Optional advanced features are exposed via :
 Multithreading is disabled by default when building with `make`.
 Enabling multithreading requires 2 conditions :
 - set macro `ZSTD_MULTITHREAD`
-- on POSIX systems : compile with pthread (`-pthread` compilation flag for `gcc` for example)
+- on POSIX systems : compile with pthread (`-pthread` compilation flag for `gcc`)
 
 Both conditions are automatically triggered by invoking `make lib-mt` target.
 Note that, when linking a POSIX program with a multithreaded version of `libzstd`,
 it's necessary to trigger `-pthread` flag during link stage.
 
-Multithreading capabilities are exposed via :
+Multithreading capabilities are exposed
-- private API `lib/compress/zstdmt_compress.h`.
+via [advanced API `ZSTD_compress_generic()` defined in `lib/zstd.h`](https://github.com/facebook/zstd/blob/dev/lib/zstd.h#L919).
-  Symbols defined in this header are currently exposed in `libzstd`, hence usable.
+This API is still considered experimental,
-  Note however that this API is planned to be locked and remain strictly internal in the future.
+but is expected to become "stable" at some point in the future.
-- advanced API `ZSTD_compress_generic()`, defined in `lib/zstd.h`, experimental section.
-  This API is still considered experimental, but is designed to be labelled "stable" at some point in the future.
-  It's the recommended entry point for multi-threading operations.
 
 
 #### Windows : using MinGW+MSYS to create DLL
@@ -92,7 +100,6 @@ The compiled executable will require ZSTD DLL which is available at `dll\libzstd
 
 Obsolete API on their way out are stored in directory `lib/deprecated`.
 At this stage, it contains older streaming prototypes, in `lib/deprecated/zbuff.h`.
-Presence in this directory is temporary.
 These prototypes will be removed in some future version.
 Consider migrating code towards supported streaming API exposed in `zstd.h`.
 

programs/fileio.c

@@ -951,10 +951,14 @@ int FIO_compressMultipleFilenames(const char** inFileNamesTable, unsigned nbFile
     if (outFileName != NULL) {
         unsigned u;
         ress.dstFile = FIO_openDstFile(outFileName);
-        for (u=0; u<nbFiles; u++)
+        if (ress.dstFile==NULL) {  /* could not open outFileName */
-            missed_files += FIO_compressFilename_srcFile(ress, outFileName, inFileNamesTable[u], compressionLevel);
+            missed_files = nbFiles;
-        if (fclose(ress.dstFile))
+        } else {
-            EXM_THROW(29, "Write error : cannot properly close stdout");
+            for (u=0; u<nbFiles; u++)
+                missed_files += FIO_compressFilename_srcFile(ress, outFileName, inFileNamesTable[u], compressionLevel);
+            if (fclose(ress.dstFile))
+                EXM_THROW(29, "Write error : cannot properly close stdout");
+        }
     } else {
         unsigned u;
         for (u=0; u<nbFiles; u++) {

tests/playTests.sh

@@ -191,6 +191,13 @@ $ZSTD -t tmp1.zst tmp2.zst
 $ZSTD -dc tmp1.zst tmp2.zst
 $ZSTD tmp1.zst tmp2.zst -o "$INTOVOID"
 $ZSTD -d tmp1.zst tmp2.zst -o tmp
+touch tmpexists
+$ZSTD tmp1 tmp2 -f -o tmpexists
+$ZSTD tmp1 tmp2 -o tmpexists && die "should have refused to overwrite"
+# Bug: PR #972
+if [ "$?" -eq 139 ]; then
+  die "should not have segfaulted"
+fi
 rm tmp*