util: add safe write functions (#22160)

* add safe write functions

* log error

* bzfile safe_fopen&safe_flush

* update test_case

* trigger ci

Co-authored-by: Willem Melching <willem.melching@gmail.com>

selfdrive/common/tests/test_util.cc

@@ -93,6 +93,24 @@ TEST_CASE("util::read_files_in_dir") {
   }
 }
 
+
+TEST_CASE("util::safe_fwrite") {
+  char filename[] = "/tmp/XXXXXX";
+  int fd = mkstemp(filename);
+  close(fd);
+  std::string dat = random_bytes(1024 * 1024);
+
+  FILE *f = util::safe_fopen(filename, "wb");
+  REQUIRE(f != nullptr);
+  size_t size = util::safe_fwrite(dat.data(), 1, dat.size(), f);
+  REQUIRE(size == dat.size());
+  int ret = util::safe_fflush(f);
+  REQUIRE(ret == 0);
+  ret = fclose(f);
+  REQUIRE(ret == 0);
+  REQUIRE(dat == util::read_file(filename));
+}
+
 TEST_CASE("util::create_directories") {
   system("rm /tmp/test_create_directories -rf");
   std::string dir = "/tmp/test_create_directories/a/b/c/d/e/f";

selfdrive/common/util.cc

@@ -107,6 +107,32 @@ int write_file(const char* path, const void* data, size_t size, int flags, mode_
   return (n >= 0 && (size_t)n == size) ? 0 : -1;
 }
 
+FILE* safe_fopen(const char* filename, const char* mode) {
+  FILE* fp = NULL;
+  do {
+    fp = fopen(filename, mode);
+  } while ((nullptr == fp) && (errno == EINTR));
+  return fp;
+}
+
+size_t safe_fwrite(const void* ptr, size_t size, size_t count, FILE* stream) {
+  size_t written = 0;
+  do {
+    size_t ret = ::fwrite((void*)((char *)ptr + written * size), size, count - written, stream);
+    if (ret == 0 && errno != EINTR) break;
+    written += ret;
+  } while (written != count);
+  return written;
+}
+
+int safe_fflush(FILE *stream) {
+  int ret = EOF;
+  do {
+    ret = fflush(stream);
+  } while ((EOF == ret) && (errno == EINTR));
+  return ret;
+}
+
 std::string readlink(const std::string &path) {
   char buff[4096];
   ssize_t len = ::readlink(path.c_str(), buff, sizeof(buff)-1);

selfdrive/common/util.h

@@ -75,6 +75,11 @@ std::string dir_name(std::string const& path);
 std::string read_file(const std::string& fn);
 std::map<std::string, std::string> read_files_in_dir(const std::string& path);
 int write_file(const char* path, const void* data, size_t size, int flags = O_WRONLY, mode_t mode = 0664);
+
+FILE* safe_fopen(const char* filename, const char* mode);
+size_t safe_fwrite(const void * ptr, size_t size, size_t count, FILE * stream);
+int safe_fflush(FILE *stream);
+
 std::string readlink(const std::string& path);
 bool file_exists(const std::string& fn);
 bool create_directories(const std::string &dir, mode_t mode);

selfdrive/loggerd/logger.h

@@ -23,7 +23,7 @@ const std::string LOG_ROOT = Path::log_root();
 class BZFile {
  public:
   BZFile(const char* path) {
-    file = fopen(path, "wb");
+    file = util::safe_fopen(path, "wb");
     assert(file != nullptr);
     int bzerror;
     bz_file = BZ2_bzWriteOpen(&bzerror, file, 9, 0, 30);
@@ -35,6 +35,7 @@ class BZFile {
     if (bzerror != BZ_OK) {
       LOGE("BZ2_bzWriteClose error, bzerror=%d", bzerror);
     }
+    util::safe_fflush(file);
     int err = fclose(file);
     assert(err == 0);
   }

selfdrive/loggerd/omx_encoder.cc

@@ -344,7 +344,10 @@ void OmxEncoder::handle_out_buf(OmxEncoder *e, OMX_BUFFERHEADERTYPE *out_buf) {
 
   if (e->of) {
     //printf("write %d flags 0x%x\n", out_buf->nFilledLen, out_buf->nFlags);
-    fwrite(buf_data, out_buf->nFilledLen, 1, e->of);
+    size_t written = util::safe_fwrite(buf_data, 1, out_buf->nFilledLen, e->of);
+    if (written != out_buf->nFilledLen) {
+      LOGE("failed to write file.errno=%d", errno);
+    }
   }
 
   if (e->remuxing) {
@@ -505,11 +508,11 @@ void OmxEncoder::encoder_open(const char* path) {
     this->wrote_codec_config = false;
   } else {
     if (this->write) {
-      this->of = fopen(this->vid_path, "wb");
+      this->of = util::safe_fopen(this->vid_path, "wb");
       assert(this->of);
 #ifndef QCOM2
       if (this->codec_config_len > 0) {
-        fwrite(this->codec_config, this->codec_config_len, 1, this->of);
+        util::safe_fwrite(this->codec_config, 1, this->codec_config_len, this->of);
       }
 #endif
     }
@@ -557,6 +560,7 @@ void OmxEncoder::encoder_close() {
       avformat_free_context(this->ofmt_ctx);
     } else {
       if (this->of) {
+        util::safe_fflush(this->of);
         fclose(this->of);
         this->of = nullptr;
       }