1 // Copyright 2015 The Chromium OS Authors. All rights reserved.
2 // Use of this source code is governed by a BSD-style license that can be
3 // found in the LICENSE file.
4 
5 #include "test_utils.h"
6 
7 #include <stdio.h>
8 #include <stdlib.h>
9 #include <string.h>
10 #include <sys/stat.h>
11 #include <unistd.h>
12 
13 #include <gtest/gtest.h>
14 #include <vector>
15 
16 using std::string;
17 using std::vector;
18 
19 namespace {
20 
21 // If |path| is absolute, or explicit relative to the current working directory,
22 // leaves it as is. Otherwise, if TMPDIR is defined in the environment and is
23 // non-empty, prepends it to |path|. Otherwise, prepends /tmp.  Returns the
24 // resulting path.
PrependTmpdir(const string & path)25 const string PrependTmpdir(const string& path) {
26   if (path[0] == '/')
27     return path;
28 
29   const char* tmpdir = getenv("TMPDIR");
30   const string prefix = (tmpdir && *tmpdir ? tmpdir : "/tmp");
31   return prefix + "/" + path;
32 }
33 
MakeTempFile(const string & base_filename_template,string * filename)34 bool MakeTempFile(const string& base_filename_template, string* filename) {
35   const string filename_template = PrependTmpdir(base_filename_template);
36   vector<char> result(filename_template.size() + 1, '\0');
37   memcpy(result.data(), filename_template.data(), filename_template.size());
38 
39   int mkstemp_fd = mkstemp(result.data());
40   if (mkstemp_fd < 0) {
41     perror("mkstemp()");
42     return false;
43   }
44   close(mkstemp_fd);
45 
46   if (filename)
47     *filename = result.data();
48   return true;
49 }
50 
51 }  // namespace
52 
53 namespace test_utils {
54 
SetUp()55 void BsdiffTestEnvironment::SetUp() {
56 #ifdef BSDIFF_TARGET_UNITTEST
57 #define BSDIFF_TARGET_TMP_BASE "/data/tmp"
58       if (access(BSDIFF_TARGET_TMP_BASE, F_OK) == -1) {
59         mkdir(BSDIFF_TARGET_TMP_BASE, S_IRWXU | S_IRWXG | S_IROTH | S_IWOTH);
60       }
61       setenv("TMPDIR", BSDIFF_TARGET_TMP_BASE, 1);
62 #endif // defined (BSDIFF_TARGET_UNITTEST)
63 }
64 
ReadFile(const string & path,vector<uint8_t> * out)65 bool ReadFile(const string& path, vector<uint8_t>* out) {
66   FILE* fp = fopen(path.c_str(), "r");
67   if (!fp)
68     return false;
69   out->clear();
70 
71   uint8_t buf[16 * 1024];
72   while (true) {
73     size_t bytes_read = fread(buf, 1, sizeof(buf), fp);
74     if (!bytes_read)
75       break;
76     out->insert(out->end(), buf, buf + bytes_read);
77   }
78   bool result = !ferror(fp);
79   fclose(fp);
80   return result;
81 }
82 
WriteFile(const string & path,vector<uint8_t> contents)83 bool WriteFile(const string& path, vector<uint8_t> contents) {
84   FILE* fp = fopen(path.c_str(), "r");
85   if (!fp)
86     return false;
87   size_t written = fwrite(contents.data(), 1, contents.size(), fp);
88   bool result = written == contents.size() && !ferror(fp);
89   fclose(fp);
90   return result;
91 }
92 
ScopedTempFile(const string & pattern)93 ScopedTempFile::ScopedTempFile(const string& pattern) {
94   EXPECT_TRUE(MakeTempFile(pattern, &filename_));
95 }
96 
~ScopedTempFile()97 ScopedTempFile::~ScopedTempFile() {
98   if (!filename_.empty() && unlink(filename_.c_str()) < 0) {
99     perror("Unable to remove temporary file");
100   }
101 }
102 
LoadFromFile(const string & filename)103 bool BsdiffPatchFile::LoadFromFile(const string& filename) {
104   vector<uint8_t> contents;
105   if (!ReadFile(filename, &contents))
106     return false;
107   file_size = contents.size();
108   // Check that the file includes at least the header.
109   TEST_AND_RETURN_FALSE(contents.size() >= kHeaderSize);
110   magic = string(contents.data(), contents.data() + 8);
111   memcpy(&ctrl_len, contents.data() + 8, sizeof(ctrl_len));
112   memcpy(&diff_len, contents.data() + 16, sizeof(diff_len));
113   memcpy(&new_file_len, contents.data() + 24, sizeof(new_file_len));
114 
115   // Sanity check before we attempt to parse the bz2 streams.
116   TEST_AND_RETURN_FALSE(ctrl_len >= 0);
117   TEST_AND_RETURN_FALSE(diff_len >= 0);
118 
119   // The cast is safe since ctrl_len and diff_len are both positive.
120   TEST_AND_RETURN_FALSE(file_size >=
121         static_cast<uint64_t>(kHeaderSize + ctrl_len + diff_len));
122   extra_len = file_size - kHeaderSize - ctrl_len - diff_len;
123 
124   uint8_t* ptr = contents.data() + kHeaderSize;
125   bz2_ctrl = vector<uint8_t>(ptr, ptr + ctrl_len);
126   ptr += ctrl_len;
127   bz2_diff = vector<uint8_t>(ptr, ptr + diff_len);
128   ptr += diff_len;
129   bz2_extra = vector<uint8_t>(ptr, ptr + extra_len);
130 
131   return true;
132 }
133 
IsValid() const134 bool BsdiffPatchFile::IsValid() const {
135   TEST_AND_RETURN_FALSE(ctrl_len >= 0);
136   TEST_AND_RETURN_FALSE(diff_len >= 0);
137   TEST_AND_RETURN_FALSE(new_file_len >= 0);
138 
139   // TODO(deymo): Test that the length of the decompressed bz2 streams |diff|
140   // plus |extra| are equal to the |new_file_len|.
141   // TODO(deymo): Test that all the |bz2_ctrl| triplets (x, y, z) have a "x"
142   // and "y" value >= 0 ("z" can be negative).
143   return true;
144 }
145 
146 }  // namespace test_utils
147