Implment more gzip compatibility (#3037)

-n --no-name is the current behavior already, so we can implement this as a noop. --best is an alias for -9 in gzip add basic cli tests.
facebook · Feb 8, 2022 · 479ef20 · 479ef20
1 parent 7e364e8
commit 479ef20
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diff --git a/programs/zstdcli.c b/programs/zstdcli.c
@@ -866,7 +866,10 @@ int main(int argCount, const char* argv[])
     if (exeNameMatch(programName, ZSTD_UNZSTD)) operation=zom_decompress;
     if (exeNameMatch(programName, ZSTD_CAT)) { operation=zom_decompress; FIO_overwriteMode(prefs); forceStdout=1; followLinks=1; outFileName=stdoutmark; g_displayLevel=1; }     /* supports multiple formats */
     if (exeNameMatch(programName, ZSTD_ZCAT)) { operation=zom_decompress; FIO_overwriteMode(prefs); forceStdout=1; followLinks=1; outFileName=stdoutmark; g_displayLevel=1; }    /* behave like zcat, also supports multiple formats */
-    if (exeNameMatch(programName, ZSTD_GZ)) { suffix = GZ_EXTENSION; FIO_setCompressionType(prefs, FIO_gzipCompression); FIO_setRemoveSrcFile(prefs, 1); }        /* behave like gzip */
+    if (exeNameMatch(programName, ZSTD_GZ)) {   /* behave like gzip */
+        suffix = GZ_EXTENSION; FIO_setCompressionType(prefs, FIO_gzipCompression); FIO_setRemoveSrcFile(prefs, 1);
+        dictCLevel = cLevel = 6;  /* gzip default is -6 */
+    }
     if (exeNameMatch(programName, ZSTD_GUNZIP)) { operation=zom_decompress; FIO_setRemoveSrcFile(prefs, 1); }                                                     /* behave like gunzip, also supports multiple formats */
     if (exeNameMatch(programName, ZSTD_GZCAT)) { operation=zom_decompress; FIO_overwriteMode(prefs); forceStdout=1; followLinks=1; outFileName=stdoutmark; g_displayLevel=1; }   /* behave like gzcat, also supports multiple formats */
     if (exeNameMatch(programName, ZSTD_LZMA)) { suffix = LZMA_EXTENSION; FIO_setCompressionType(prefs, FIO_lzmaCompression); FIO_setRemoveSrcFile(prefs, 1); }    /* behave like lzma */
@@ -936,6 +939,10 @@ int main(int argCount, const char* argv[])
                 if (!strcmp(argument, "--format=zstd")) { suffix = ZSTD_EXTENSION; FIO_setCompressionType(prefs, FIO_zstdCompression); continue; }
 #ifdef ZSTD_GZCOMPRESS
                 if (!strcmp(argument, "--format=gzip")) { suffix = GZ_EXTENSION; FIO_setCompressionType(prefs, FIO_gzipCompression); continue; }
+                if (exeNameMatch(programName, ZSTD_GZ)) {     /* behave like gzip */
+                    if (!strcmp(argument, "--best")) { dictCLevel = cLevel = 9; continue; }
+                    if (!strcmp(argument, "--no-name")) { /* ignore for now */; continue; }
+                }
 #endif
 #ifdef ZSTD_LZMACOMPRESS
                 if (!strcmp(argument, "--format=lzma")) { suffix = LZMA_EXTENSION; FIO_setCompressionType(prefs, FIO_lzmaCompression);  continue; }
@@ -1098,6 +1105,9 @@ int main(int argCount, const char* argv[])
                     /* Force stdout, even if stdout==console */
                 case 'c': forceStdout=1; outFileName=stdoutmark; argument++; break;
 
+                    /* do not store filename - gzip compatibility - nothing to do */
+                case 'n': argument++; break;
+
                     /* Use file content as dictionary */
                 case 'D': argument++; NEXT_FIELD(dictFileName); break;
 

diff --git a/tests/cli-tests/compression/gzip-compat.sh b/tests/cli-tests/compression/gzip-compat.sh
@@ -0,0 +1,17 @@
+#!/bin/sh
+
+set -e
+
+# Uncomment the set -v line for debugging
+# set -v
+
+# Test gzip specific compression option
+gzip --fast file ; gzip -d file.gz
+gzip --best file ; gzip -d file.gz
+
+# Test -n / --no-name: do not embed original filename in archive
+gzip -n file           ; grep -qv file file.gz  ; gzip -d file.gz
+gzip --no-name file    ; grep -qv file file.gz  ; gzip -d file.gz
+gzip -c --no-name file | grep -qv file
+
+rm -f gzip