Add libziparchive-based unzip.

Bug: N/A
Test: new toybox unzip.test
Change-Id: I00be388578be9a0a0390a9e2ecfac664c6ab39ca

6 files changed, 407 insertions, 23 deletions

diff --git a/include/ziparchive/zip_archive.h b/include/ziparchive/zip_archive.h
index 31fc2dfc9..ece86931a 100644
--- a/include/ziparchive/zip_archive.h
+++ b/include/ziparchive/zip_archive.h
@@ -71,8 +71,17 @@ struct ZipEntry {
   // Modification time. The zipfile format specifies
   // that the first two little endian bytes contain the time
   // and the last two little endian bytes contain the date.
+  // See `GetModificationTime`.
+  // TODO: should be overridden by extra time field, if present.
   uint32_t mod_time;
 
+  // Returns `mod_time` as a broken-down struct tm.
+  struct tm GetModificationTime() const;
+
+  // Suggested Unix mode for this entry, from the zip archive if created on
+  // Unix, or a default otherwise.
+  mode_t unix_mode;
+
   // 1 if this entry contains a data descriptor segment, 0
   // otherwise.
   uint8_t has_data_descriptor;
diff --git a/libziparchive/Android.bp b/libziparchive/Android.bp
index 287a99c60..1084d59e5 100644
--- a/libziparchive/Android.bp
+++ b/libziparchive/Android.bp
@@ -52,17 +52,25 @@ cc_defaults {
     ],
 }
 
-
 cc_library {
     name: "libziparchive",
     host_supported: true,
-    vendor_available:true,
+    vendor_available: true,
 
-    defaults: ["libziparchive_defaults", "libziparchive_flags"],
-    shared_libs: ["liblog", "libbase"],
+    defaults: [
+        "libziparchive_defaults",
+        "libziparchive_flags",
+    ],
+    shared_libs: [
+        "liblog",
+        "libbase",
+    ],
     target: {
         android: {
-            shared_libs: ["libz", "libutils"],
+            shared_libs: [
+                "libz",
+                "libutils",
+            ],
         },
         host: {
             static_libs: ["libutils"],
@@ -88,7 +96,10 @@ cc_library {
     name: "libziparchive-host",
     host_supported: true,
     device_supported: false,
-    defaults: ["libziparchive_defaults", "libziparchive_flags"],
+    defaults: [
+        "libziparchive_defaults",
+        "libziparchive_flags",
+    ],
     shared_libs: ["libz-host"],
     static_libs: ["libutils"],
 }
@@ -150,3 +161,13 @@ cc_benchmark {
         },
     },
 }
+
+cc_binary {
+    name: "unzip",
+    defaults: ["libziparchive_flags"],
+    srcs: ["unzip.cpp"],
+    shared_libs: [
+        "libbase",
+        "libziparchive",
+    ],
+}
diff --git a/libziparchive/unzip.cpp b/libziparchive/unzip.cpp
new file mode 100644
index 000000000..6756007af
--- /dev/null
+++ b/libziparchive/unzip.cpp
@@ -0,0 +1,345 @@
+/*
+ * Copyright (C) 2017 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include <errno.h>
+#include <error.h>
+#include <fcntl.h>
+#include <getopt.h>
+#include <inttypes.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <time.h>
+#include <unistd.h>
+
+#include <set>
+#include <string>
+
+#include <android-base/file.h>
+#include <android-base/strings.h>
+#include <ziparchive/zip_archive.h>
+
+enum OverwriteMode {
+  kAlways,
+  kNever,
+  kPrompt,
+};
+
+static OverwriteMode overwrite_mode = kPrompt;
+static const char* flag_d = nullptr;
+static bool flag_l = false;
+static bool flag_p = false;
+static bool flag_q = false;
+static bool flag_v = false;
+static const char* archive_name = nullptr;
+static std::set<std::string> includes;
+static std::set<std::string> excludes;
+static uint64_t total_uncompressed_length = 0;
+static uint64_t total_compressed_length = 0;
+static size_t file_count = 0;
+
+static bool Filter(const std::string& name) {
+  if (!excludes.empty() && excludes.find(name) != excludes.end()) return true;
+  if (!includes.empty() && includes.find(name) == includes.end()) return true;
+  return false;
+}
+
+static bool MakeDirectoryHierarchy(const std::string& path) {
+  // stat rather than lstat because a symbolic link to a directory is fine too.
+  struct stat sb;
+  if (stat(path.c_str(), &sb) != -1 && S_ISDIR(sb.st_mode)) return true;
+
+  // Ensure the parent directories exist first.
+  if (!MakeDirectoryHierarchy(android::base::Dirname(path))) return false;
+
+  // Then try to create this directory.
+  return (mkdir(path.c_str(), 0777) != -1);
+}
+
+static int CompressionRatio(int64_t uncompressed, int64_t compressed) {
+  if (uncompressed == 0) return 0;
+  return (100LL * (uncompressed - compressed)) / uncompressed;
+}
+
+static void MaybeShowHeader() {
+  if (!flag_q) printf("Archive:  %s\n", archive_name);
+  if (flag_v) {
+    printf(
+        " Length   Method    Size  Cmpr    Date    Time   CRC-32   Name\n"
+        "--------  ------  ------- ---- ---------- ----- --------  ----\n");
+  } else if (flag_l) {
+    printf(
+        "  Length      Date    Time    Name\n"
+        "---------  ---------- -----   ----\n");
+  }
+}
+
+static void MaybeShowFooter() {
+  if (flag_v) {
+    printf(
+        "--------          -------  ---                            -------\n"
+        "%8" PRId64 "         %8" PRId64 " %3d%%                            %zu file%s\n",
+        total_uncompressed_length, total_compressed_length,
+        CompressionRatio(total_uncompressed_length, total_compressed_length), file_count,
+        (file_count == 1) ? "" : "s");
+  } else if (flag_l) {
+    printf(
+        "---------                     -------\n"
+        "%9" PRId64 "                     %zu file%s\n",
+        total_uncompressed_length, file_count, (file_count == 1) ? "" : "s");
+  }
+}
+
+static bool PromptOverwrite(const std::string& dst) {
+  // TODO: [r]ename not implemented because it doesn't seem useful.
+  printf("replace %s? [y]es, [n]o, [A]ll, [N]one: ", dst.c_str());
+  fflush(stdout);
+  while (true) {
+    char* line = nullptr;
+    size_t n;
+    if (getline(&line, &n, stdin) == -1) {
+      error(1, 0, "(EOF/read error; assuming [N]one...)");
+      overwrite_mode = kNever;
+      return false;
+    }
+    if (n == 0) continue;
+    char cmd = line[0];
+    free(line);
+    switch (cmd) {
+      case 'y':
+        return true;
+      case 'n':
+        return false;
+      case 'A':
+        overwrite_mode = kAlways;
+        return true;
+      case 'N':
+        overwrite_mode = kNever;
+        return false;
+    }
+  }
+}
+
+static void ExtractToPipe(ZipArchiveHandle zah, ZipEntry& entry, const std::string& name) {
+  // We need to extract to memory because ExtractEntryToFile insists on
+  // being able to seek and truncate, and you can't do that with stdout.
+  uint8_t* buffer = new uint8_t[entry.uncompressed_length];
+  int err = ExtractToMemory(zah, &entry, buffer, entry.uncompressed_length);
+  if (err < 0) {
+    error(1, 0, "failed to extract %s: %s", name.c_str(), ErrorCodeString(err));
+  }
+  if (!android::base::WriteFully(1, buffer, entry.uncompressed_length)) {
+    error(1, errno, "failed to write %s to stdout", name.c_str());
+  }
+  delete[] buffer;
+}
+
+static void ExtractOne(ZipArchiveHandle zah, ZipEntry& entry, const std::string& name) {
+  // Bad filename?
+  if (android::base::StartsWith(name, "/") || android::base::StartsWith(name, "../") ||
+      name.find("/../") != std::string::npos) {
+    error(1, 0, "bad filename %s", name.c_str());
+  }
+
+  // Where are we actually extracting to (for human-readable output)?
+  std::string dst;
+  if (flag_d) {
+    dst = flag_d;
+    if (!android::base::EndsWith(dst, "/")) dst += '/';
+  }
+  dst += name;
+
+  // Ensure the directory hierarchy exists.
+  if (!MakeDirectoryHierarchy(android::base::Dirname(name))) {
+    error(1, errno, "couldn't create directory hierarchy for %s", dst.c_str());
+  }
+
+  // An entry in a zip file can just be a directory itself.
+  if (android::base::EndsWith(name, "/")) {
+    if (mkdir(name.c_str(), entry.unix_mode) == -1) {
+      // If the directory already exists, that's fine.
+      if (errno == EEXIST) {
+        struct stat sb;
+        if (stat(name.c_str(), &sb) != -1 && S_ISDIR(sb.st_mode)) return;
+      }
+      error(1, errno, "couldn't extract directory %s", dst.c_str());
+    }
+    return;
+  }
+
+  // Create the file.
+  int fd = open(name.c_str(), O_CREAT | O_WRONLY | O_CLOEXEC | O_EXCL, entry.unix_mode);
+  if (fd == -1 && errno == EEXIST) {
+    if (overwrite_mode == kNever) return;
+    if (overwrite_mode == kPrompt && !PromptOverwrite(dst)) return;
+    // Either overwrite_mode is kAlways or the user consented to this specific case.
+    fd = open(name.c_str(), O_WRONLY | O_CREAT | O_CLOEXEC | O_TRUNC, entry.unix_mode);
+  }
+  if (fd == -1) error(1, errno, "couldn't create file %s", dst.c_str());
+
+  // Actually extract into the file.
+  if (!flag_q) printf("  inflating: %s\n", dst.c_str());
+  int err = ExtractEntryToFile(zah, &entry, fd);
+  if (err < 0) error(1, 0, "failed to extract %s: %s", dst.c_str(), ErrorCodeString(err));
+  close(fd);
+}
+
+static void ListOne(const ZipEntry& entry, const std::string& name) {
+  tm t = entry.GetModificationTime();
+  char time[32];
+  snprintf(time, sizeof(time), "%04d-%02d-%02d %02d:%02d", t.tm_year + 1900, t.tm_mon + 1,
+           t.tm_mday, t.tm_hour, t.tm_min);
+  if (flag_v) {
+    printf("%8d  %s  %7d %3d%% %s %08x  %s\n", entry.uncompressed_length,
+           (entry.method == kCompressStored) ? "Stored" : "Defl:N", entry.compressed_length,
+           CompressionRatio(entry.uncompressed_length, entry.compressed_length), time, entry.crc32,
+           name.c_str());
+  } else {
+    printf("%9d  %s   %s\n", entry.uncompressed_length, time, name.c_str());
+  }
+}
+
+static void ProcessOne(ZipArchiveHandle zah, ZipEntry& entry, const std::string& name) {
+  if (flag_l || flag_v) {
+    // -l or -lv or -lq or -v.
+    ListOne(entry, name);
+  } else {
+    // Actually extract.
+    if (flag_p) {
+      ExtractToPipe(zah, entry, name);
+    } else {
+      ExtractOne(zah, entry, name);
+    }
+  }
+  total_uncompressed_length += entry.uncompressed_length;
+  total_compressed_length += entry.compressed_length;
+  ++file_count;
+}
+
+static void ProcessAll(ZipArchiveHandle zah) {
+  MaybeShowHeader();
+
+  // libziparchive iteration order doesn't match the central directory.
+  // We could sort, but that would cost extra and wouldn't match either.
+  void* cookie;
+  int err = StartIteration(zah, &cookie, nullptr, nullptr);
+  if (err != 0) {
+    error(1, 0, "couldn't iterate %s: %s", archive_name, ErrorCodeString(err));
+  }
+
+  ZipEntry entry;
+  ZipString string;
+  while ((err = Next(cookie, &entry, &string)) >= 0) {
+    std::string name(string.name, string.name + string.name_length);
+    if (!Filter(name)) ProcessOne(zah, entry, name);
+  }
+
+  if (err < -1) error(1, 0, "failed iterating %s: %s", archive_name, ErrorCodeString(err));
+  EndIteration(cookie);
+
+  MaybeShowFooter();
+}
+
+static void ShowHelp(bool full) {
+  fprintf(full ? stdout : stderr, "usage: unzip [-d DIR] [-lnopqv] ZIP [FILE...] [-x FILE...]\n");
+  if (!full) exit(EXIT_FAILURE);
+
+  printf(
+      "\n"
+      "Extract FILEs from ZIP archive. Default is all files.\n"
+      "\n"
+      "-d DIR	Extract into DIR\n"
+      "-l	List contents (-lq excludes archive name, -lv is verbose)\n"
+      "-n	Never overwrite files (default: prompt)\n"
+      "-o	Always overwrite files\n"
+      "-p	Pipe to stdout\n"
+      "-q	Quiet\n"
+      "-v	List contents verbosely\n"
+      "-x FILE	Exclude files\n");
+  exit(EXIT_SUCCESS);
+}
+
+int main(int argc, char* argv[]) {
+  static struct option opts[] = {
+      {"help", no_argument, 0, 'h'},
+  };
+  bool saw_x = false;
+  int opt;
+  while ((opt = getopt_long(argc, argv, "-d:hlnopqvx", opts, nullptr)) != -1) {
+    switch (opt) {
+      case 'd':
+        flag_d = optarg;
+        break;
+      case 'h':
+        ShowHelp(true);
+        break;
+      case 'l':
+        flag_l = true;
+        break;
+      case 'n':
+        overwrite_mode = kNever;
+        break;
+      case 'o':
+        overwrite_mode = kAlways;
+        break;
+      case 'p':
+        flag_p = flag_q = true;
+        break;
+      case 'q':
+        flag_q = true;
+        break;
+      case 'v':
+        flag_v = true;
+        break;
+      case 'x':
+        saw_x = true;
+        break;
+      case 1:
+        // -x swallows all following arguments, so we use '-' in the getopt
+        // string and collect files here.
+        if (!archive_name) {
+          archive_name = optarg;
+        } else if (saw_x) {
+          excludes.insert(optarg);
+        } else {
+          includes.insert(optarg);
+        }
+        break;
+      default:
+        ShowHelp(false);
+    }
+  }
+
+  if (!archive_name) error(1, 0, "missing archive filename");
+
+  // We can't support "-" to unzip from stdin because libziparchive relies on mmap.
+  ZipArchiveHandle zah;
+  int32_t err;
+  if ((err = OpenArchive(archive_name, &zah)) != 0) {
+    error(1, 0, "couldn't open %s: %s", archive_name, ErrorCodeString(err));
+  }
+
+  // Implement -d by changing into that directory.
+  // We'll create implicit directories based on paths in the zip file, but we
+  // require that the -d directory already exists.
+  if (flag_d && chdir(flag_d) == -1) error(1, errno, "couldn't chdir to %s", flag_d);
+
+  ProcessAll(zah);
+
+  CloseArchive(zah);
+  return 0;
+}
diff --git a/libziparchive/zip_archive.cc b/libziparchive/zip_archive.cc
index 246575f81..6860c4e2d 100644
--- a/libziparchive/zip_archive.cc
+++ b/libziparchive/zip_archive.cc
@@ -27,6 +27,7 @@
 #include <limits.h>
 #include <stdlib.h>
 #include <string.h>
+#include <time.h>
 #include <unistd.h>
 
 #include <memory>
@@ -589,6 +590,13 @@ static int32_t FindEntry(const ZipArchive* archive, const int ent,
     data->has_data_descriptor = 1;
   }
 
+  // 4.4.2.1: the upper byte of `version_made_by` gives the source OS. Unix is 3.
+  if ((cdr->version_made_by >> 8) == 3) {
+    data->unix_mode = (cdr->external_file_attributes >> 16) & 0xffff;
+  } else {
+    data->unix_mode = 0777;
+  }
+
   // Check that the local file header name matches the declared
   // name in the central directory.
   if (lfh->file_name_length == nameLen) {
@@ -1227,3 +1235,17 @@ bool ZipArchive::InitializeCentralDirectory(const char* debug_file_name, off64_t
   }
   return true;
 }
+
+tm ZipEntry::GetModificationTime() const {
+  tm t = {};
+
+  t.tm_hour = (mod_time >> 11) & 0x1f;
+  t.tm_min = (mod_time >> 5) & 0x3f;
+  t.tm_sec = (mod_time & 0x1f) << 1;
+
+  t.tm_year = ((mod_time >> 25) & 0x7f) + 80;
+  t.tm_mon = ((mod_time >> 21) & 0xf) - 1;
+  t.tm_mday = (mod_time >> 16) & 0x1f;
+
+  return t;
+}
diff --git a/libziparchive/zip_archive_common.h b/libziparchive/zip_archive_common.h
index ca4250942..bc1ebb429 100644
--- a/libziparchive/zip_archive_common.h
+++ b/libziparchive/zip_archive_common.h
@@ -73,7 +73,7 @@ struct CentralDirectoryRecord {
 
   // The start of record signature. Must be |kSignature|.
   uint32_t record_signature;
-  // Tool version. Ignored by this implementation.
+  // Source tool version. Top byte gives source OS.
   uint16_t version_made_by;
   // Tool version. Ignored by this implementation.
   uint16_t version_needed;
@@ -106,7 +106,7 @@ struct CentralDirectoryRecord {
   uint16_t file_start_disk;
   // File attributes. Ignored by this implementation.
   uint16_t internal_file_attributes;
-  // File attributes. Ignored by this implementation.
+  // File attributes. For archives created on Unix, the top bits are the mode.
   uint32_t external_file_attributes;
   // The offset to the local file header for this entry, from the
   // beginning of this archive.
diff --git a/libziparchive/zip_writer_test.cc b/libziparchive/zip_writer_test.cc
index 5b526a4f8..9ad025255 100644
--- a/libziparchive/zip_writer_test.cc
+++ b/libziparchive/zip_writer_test.cc
@@ -135,17 +135,6 @@ TEST_F(zipwriter, WriteUncompressedZipFileWithAlignedFlag) {
   CloseArchive(handle);
 }
 
-static void ConvertZipTimeToTm(uint32_t& zip_time, struct tm* tm) {
-  memset(tm, 0, sizeof(struct tm));
-  tm->tm_hour = (zip_time >> 11) & 0x1f;
-  tm->tm_min = (zip_time >> 5) & 0x3f;
-  tm->tm_sec = (zip_time & 0x1f) << 1;
-
-  tm->tm_year = ((zip_time >> 25) & 0x7f) + 80;
-  tm->tm_mon = ((zip_time >> 21) & 0xf) - 1;
-  tm->tm_mday = (zip_time >> 16) & 0x1f;
-}
-
 static struct tm MakeTm() {
   struct tm tm;
   memset(&tm, 0, sizeof(struct tm));
@@ -177,8 +166,7 @@ TEST_F(zipwriter, WriteUncompressedZipFileWithAlignedFlagAndTime) {
   ASSERT_EQ(0, FindEntry(handle, ZipString("align.txt"), &data));
   EXPECT_EQ(0, data.offset & 0x03);
 
-  struct tm mod;
-  ConvertZipTimeToTm(data.mod_time, &mod);
+  struct tm mod = data.GetModificationTime();
   EXPECT_EQ(tm.tm_sec, mod.tm_sec);
   EXPECT_EQ(tm.tm_min, mod.tm_min);
   EXPECT_EQ(tm.tm_hour, mod.tm_hour);
@@ -228,8 +216,7 @@ TEST_F(zipwriter, WriteUncompressedZipFileWithAlignedValueAndTime) {
   ASSERT_EQ(0, FindEntry(handle, ZipString("align.txt"), &data));
   EXPECT_EQ(0, data.offset & 0xfff);
 
-  struct tm mod;
-  ConvertZipTimeToTm(data.mod_time, &mod);
+  struct tm mod = data.GetModificationTime();
   EXPECT_EQ(tm.tm_sec, mod.tm_sec);
   EXPECT_EQ(tm.tm_min, mod.tm_min);
   EXPECT_EQ(tm.tm_hour, mod.tm_hour);