Refactor ZIP implementation of ijar

It extracts Zip/Unzip methods of ijar in a separate
library. A zipper binary is provided to test that
implementation outside. Note that this implementation
does not compute CRC-32 and unzip will complain on
file zipped with it (but Java won't complain).

The error handling has been replaced to use proper error
reporting instead of launching abort()'s allover the place
so ijar's zip library can be used outside of ijar.

Finally, support for ZIP preamble has been added to
handle self-extractable ZIP files.

--
Change-Id: I833034b4c0054925bada75102fe040db875da789
Reviewed-on: https://bazel-review.googlesource.com/#/c/1371/
MOS_MIGRATED_REVID=94656262

1 files changed, 299 insertions, 0 deletions

diff --git a/third_party/ijar/zip_main.cc b/third_party/ijar/zip_main.cc
new file mode 100644
index 0000000000..8436da40f2
--- /dev/null
+++ b/third_party/ijar/zip_main.cc
@@ -0,0 +1,299 @@
+// Copyright 2015 Google Inc. All rights reserved.
+//
+// Author: Alan Donovan <adonovan@google.com>
+//
+// 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.
+
+//
+// Zip / Unzip file using ijar zip implementation.
+//
+// Note that this Zip implementation intentionally don't compute CRC-32
+// because it is useless computation for jar because Java doesn't care.
+// CRC-32 of all files in the zip file will be set to 0.
+//
+
+#include <stdio.h>
+#include <string.h>
+#include <stdlib.h>
+#include <limits.h>
+#include <fcntl.h>
+#include <unistd.h>
+#include <sys/mman.h>
+#include <errno.h>
+#include <memory>
+
+#include "third_party/ijar/zip.h"
+
+namespace devtools_ijar {
+
+#define SYSCALL(expr)  do { \
+                         if ((expr) < 0) { \
+                           perror(#expr); \
+                           abort(); \
+                         } \
+                       } while (0)
+
+//
+// A ZipExtractorProcessor that extract all files in the ZIP file.
+//
+class UnzipProcessor : public ZipExtractorProcessor {
+ public:
+  // Create a processor who will extract the files into output_root
+  // if "extract" is set to true and will print the list of files and
+  // their unix modes if "verbose" is set to true.
+  UnzipProcessor(const char *output_root, bool verbose, bool extract)
+    : output_root_(output_root), verbose_(verbose), extract_(extract) {}
+  virtual ~UnzipProcessor() {}
+
+  virtual void Process(const char* filename, const u4 attr,
+                       const u1* data, const size_t size);
+  virtual bool Accept(const char* filename, const u4 attr) {
+    return true;
+  }
+
+ private:
+  const char *output_root_;
+  const bool verbose_;
+  const bool extract_;
+};
+
+// Concatene 2 path, path1 and path2, using / as a directory separator and
+// puting the result in "out". "size" specify the size of the output buffer
+void concat_path(char* out, const size_t size,
+                 const char *path1, const char *path2) {
+  int len1 = strlen(path1);
+  int len2 = strlen(path2);
+  int l = len1;
+  strncpy(out, path1, size-1);
+  out[size-1] = 0;
+  if (l < size - 1 && path1[len1] != '/' && path2[0] != '/') {
+    out[l] = '/';
+    l++;
+    out[l] = 0;
+  }
+  if (l < size - 1) {
+    strncat(out, path2, size - 1 - l);
+  }
+}
+
+// Do a recursive mkdir of all folders of path except the last path
+// segment (if path ends with a / then the last path segment is empty).
+// All folders are created using "mode" for creation mode.
+void mkdirs(const char *path, mode_t mode) {
+  char path_[PATH_MAX];
+  struct stat statst;
+  strncpy(path_, path, PATH_MAX);
+  path_[PATH_MAX-1] = 0;
+  char *pointer = path_;
+  while ((pointer = strchr(pointer, '/')) != NULL) {
+    if (path_ != pointer) {  // skip leading slash
+      *pointer = 0;
+      if (stat(path_, &statst) != 0) {
+        if (mkdir(path_, mode) < 0) {
+          fprintf(stderr, "Cannot create folder %s: %s\n",
+                  path_, strerror(errno));
+          abort();
+        }
+      }
+      *pointer = '/';
+    }
+    pointer++;
+  }
+}
+
+void UnzipProcessor::Process(const char* filename, const u4 attr,
+                             const u1* data, const size_t size) {
+  mode_t mode = zipattr_to_mode(attr);
+  mode_t perm = mode & 0777;
+  bool isdir = (mode & S_IFDIR) != 0;
+  if (verbose_) {
+    printf("%c %O %s\n", isdir ? 'd' : 'f', perm, filename);
+  }
+  if (extract_) {
+    char path[PATH_MAX];
+    int fd;
+    concat_path(path, PATH_MAX, output_root_, filename);
+    mkdirs(path, perm);
+    if (!isdir) {
+      fd = open(path, O_CREAT | O_WRONLY, perm);
+      if (fd < 0) {
+        fprintf(stderr, "Cannot open file %s for writing: %s\n",
+                path, strerror(errno));
+        abort();
+      }
+      SYSCALL(write(fd, data, size));
+      SYSCALL(close(fd));
+    }
+  }
+}
+
+// Get the basename of path and store it in output. output_size
+// is the size of the output buffer.
+void basename(const char *path, char *output, size_t output_size) {
+  const char *pointer = strrchr(path, '/');
+  if (pointer == NULL) {
+    pointer = path;
+  }
+  strncpy(output, pointer, output_size);
+  output[output_size-1] = 0;
+}
+
+
+// Execute the extraction (or just listing if just v is provided)
+int extract(char *zipfile, bool verbose, bool extract) {
+  char output_root[PATH_MAX];
+  getcwd(output_root, PATH_MAX);
+
+  UnzipProcessor processor(output_root, verbose, extract);
+  std::unique_ptr<ZipExtractor> extractor(ZipExtractor::Create(zipfile,
+                                                               &processor));
+  if (extractor.get() == NULL) {
+    fprintf(stderr, "Unable to open zip file %s: %s.\n", zipfile,
+            strerror(errno));
+    return -1;
+  }
+
+  if (extractor->ProcessAll() < 0) {
+    fprintf(stderr, "%s.\n", extractor->GetError());
+    return -1;
+  }
+  return 0;
+}
+
+// Execute the create operation
+int create(char *zipfile, char **files, bool flatten, bool verbose) {
+  struct stat statst;
+  u8 size = ZipBuilder::EstimateSize(files);
+  if (size == 0) {
+    return -1;
+  }
+  std::unique_ptr<ZipBuilder> builder(ZipBuilder::Create(zipfile, size));
+  if (builder.get() == NULL) {
+    fprintf(stderr, "Unable to create zip file %s: %s.\n",
+            zipfile, strerror(errno));
+    return -1;
+  }
+  for (int i = 0; files[i] != NULL; i++) {
+    stat(files[i], &statst);
+    char path[PATH_MAX];
+    bool isdir = (statst.st_mode & S_IFDIR) != 0;
+
+    if (flatten && isdir) {
+      continue;
+    }
+
+    // Compute the path, flattening it if requested
+    if (flatten) {
+      basename(files[i], path, PATH_MAX);
+    } else {
+      strncpy(path, files[i], PATH_MAX);
+      path[PATH_MAX-1] = 0;
+      size_t len = strlen(path);
+      if (isdir && len < PATH_MAX - 1) {
+        // Add the trailing slash for folders
+        path[len] = '/';
+        path[len+1] = 0;
+      }
+    }
+
+    if (verbose) {
+      mode_t perm = statst.st_mode & 0777;
+      printf("%c %O %s\n", isdir ? 'd' : 'f', perm, path);
+    }
+
+    u1 *buffer = builder->NewFile(path, mode_to_zipattr(statst.st_mode));
+    if (isdir) {
+      builder->FinishFile(0);
+    } else {
+      // mmap the input file and memcpy
+      int fd = open(files[i], O_RDONLY);
+      if (fd < 0) {
+        fprintf(stderr, "Can't open file %s for reading: %s.\n",
+                files[i], strerror(errno));
+        return -1;
+      }
+      void *data = mmap(NULL, statst.st_size, PROT_READ, MAP_PRIVATE, fd, 0);
+      if (data == MAP_FAILED) {
+        fprintf(stderr, "Can't mmap file %s for reading: %s.\n",
+                files[i], strerror(errno));
+        return -1;
+      }
+      memcpy(buffer, data, statst.st_size);
+      munmap(data, statst.st_size);
+      builder->FinishFile(statst.st_size);
+    }
+  }
+  if (builder->Finish() < 0) {
+    fprintf(stderr, "%s\n", builder->GetError());
+    return -1;
+  }
+  return 0;
+}
+
+}  // namespace devtools_ijar
+
+//
+// main method
+//
+static void usage(char *progname) {
+  fprintf(stderr, "Usage: %s [vxc[f]] x.zip [file1...filen]\n", progname);
+  fprintf(stderr, "  v verbose - list all file in x.zip\n");
+  fprintf(stderr, "  x extract - extract file in x.zip in current directory\n");
+  fprintf(stderr, "  c create  - add files to x.zip\n");
+  fprintf(stderr, "  f flatten - flatten files to use with create operation\n");
+  fprintf(stderr, "x and c cannot be used in the same command-line.\n");
+  exit(1);
+}
+
+int main(int argc, char **argv) {
+  bool extract = false;
+  bool verbose = false;
+  bool create = false;
+  bool flatten = false;
+
+  if (argc < 3) {
+    usage(argv[0]);
+  }
+
+  for (int i = 0; argv[1][i] != 0; i++) {
+    switch (argv[1][i]) {
+    case 'x':
+      extract = true;
+      break;
+    case 'v':
+      verbose = true;
+      break;
+    case 'c':
+      create = true;
+      break;
+    case 'f':
+      flatten = true;
+      break;
+    default:
+      usage(argv[0]);
+    }
+  }
+  if (create) {
+    if (extract) {
+      usage(argv[0]);
+    }
+    // Create a zip
+    return devtools_ijar::create(argv[2], argv+3, flatten, verbose);
+  } else {
+    if (flatten) {
+      usage(argv[0]);
+    }
+    // Extraction / list mode
+    return devtools_ijar::extract(argv[2], verbose, extract);
+  }
+}