calculate file and directory size (#197)

* calculate file and directory size

Signed-off-by: Karsten Knese <karsten@openrobotics.org>

* fix typo

Signed-off-by: Karsten Knese <karsten@openrobotics.org>

* more error handling

Signed-off-by: Karsten Knese <karsten@openrobotics.org>

* not a

Signed-off-by: Karsten Knese <karsten@openrobotics.org>

include/rcutils/filesystem.h

@@ -167,6 +167,27 @@ RCUTILS_PUBLIC
 bool
 rcutils_mkdir(const char * abs_path);
 
+/// Calculate the size of the specified directory.
+/*
+ * Calculates the size of a directory by summarizing the file size of all files.
+ * \note This operation is not recursive.
+ * \param[in] directory_path The directory path to calculate the size of.
+ * \param[in] allocator Allocator being used for internal file path composition.
+ * \return The size of the directory in bytes.
+ */
+RCUTILS_PUBLIC
+size_t
+rcutils_calculate_directory_size(const char * directory_path, rcutils_allocator_t allocator);
+
+/// Calculate the size of the specifed file.
+/*
+ * \param[in] file_path The path of the file to obtain its size of.
+ * \return The size of the file in bytes.
+ */
+RCUTILS_PUBLIC
+size_t
+rcutils_get_file_size(const char * file_path);
+
 #ifdef __cplusplus
 }
 #endif

src/filesystem.c

@@ -24,8 +24,10 @@ extern "C"
 #include <string.h>
 #include <sys/stat.h>
 #ifndef _WIN32
+#include <dirent.h>
 #include <unistd.h>
 #else
+#include <windows.h>
 #include <direct.h>
 #endif  // _WIN32
 
@@ -210,6 +212,69 @@ rcutils_mkdir(const char * abs_path)
   return success;
 }
 
+size_t
+rcutils_calculate_directory_size(const char * directory_path, rcutils_allocator_t allocator)
+{
+  size_t dir_size = 0;
+
+  if (!rcutils_is_directory(directory_path)) {
+    fprintf(stderr, "Path is not a directory: %s\n", directory_path);
+    return dir_size;
+  }
+#ifdef _WIN32
+  char * path = rcutils_join_path(directory_path, "*", allocator);
+  WIN32_FIND_DATA data;
+  HANDLE handle = FindFirstFile(path, &data);
+  if (INVALID_HANDLE_VALUE == handle) {
+    fprintf(stderr, "Can't open directory %s. Error code: %lu\n", directory_path, GetLastError());
+    return dir_size;
+  }
+  allocator.deallocate(path, allocator.state);
+  if (handle != INVALID_HANDLE_VALUE) {
+    do {
+      // Skip over local folder handle (`.`) and parent folder (`..`)
+      if (strcmp(data.cFileName, ".") != 0 && strcmp(data.cFileName, "..") != 0) {
+        char * file_path = rcutils_join_path(directory_path, data.cFileName, allocator);
+        dir_size += rcutils_get_file_size(file_path);
+        allocator.deallocate(file_path, allocator.state);
+      }
+    } while (FindNextFile(handle, &data));
+    FindClose(handle);
+  }
+  return dir_size;
+#else
+  DIR * dir = opendir(directory_path);
+  if (NULL == dir) {
+    fprintf(stderr, "Can't open directory %s. Error code: %d\n", directory_path, errno);
+    return dir_size;
+  }
+  struct dirent * entry;
+  while (NULL != (entry = readdir(dir))) {
+    // Skip over local folder handle (`.`) and parent folder (`..`)
+    if (strcmp(entry->d_name, ".") != 0 && strcmp(entry->d_name, "..") != 0) {
+      char * file_path = rcutils_join_path(directory_path, entry->d_name, allocator);
+      dir_size += rcutils_get_file_size(file_path);
+      allocator.deallocate(file_path, allocator.state);
+    }
+  }
+  closedir(dir);
+  return dir_size;
+#endif
+}
+
+size_t
+rcutils_get_file_size(const char * file_path)
+{
+  if (!rcutils_is_file(file_path)) {
+    fprintf(stderr, "Path is not a file: %s\n", file_path);
+    return 0;
+  }
+
+  struct stat stat_buffer;
+  int rc = stat(file_path, &stat_buffer);
+  return rc == 0 ? (size_t)(stat_buffer.st_size) : 0;
+}
+
 #ifdef __cplusplus
 }
 #endif

test/dummy_folder/dummy.dummy

@@ -0,0 +1 @@
+ROS2

test/dummy_readable_file.txt

@@ -0,0 +1 @@
+ROS2

test/test_filesystem.cpp

@@ -280,3 +280,38 @@ TEST_F(TestFilesystemFixture, mkdir) {
     ASSERT_FALSE(rcutils_mkdir(path2));
   }
 }
+
+TEST_F(TestFilesystemFixture, calculate_directory_size) {
+  char * path =
+    rcutils_join_path(this->test_path, "dummy_folder", g_allocator);
+  size_t size = rcutils_calculate_directory_size(path, g_allocator);
+  ASSERT_EQ(5u, size);
+  OSRF_TESTING_TOOLS_CPP_SCOPE_EXIT({
+    g_allocator.deallocate(path, g_allocator.state);
+  });
+
+  char * non_existing_path = rcutils_join_path(this->test_path, "non_existing_folder", g_allocator);
+  size = rcutils_calculate_directory_size(non_existing_path, g_allocator);
+  ASSERT_EQ(0u, size);
+  OSRF_TESTING_TOOLS_CPP_SCOPE_EXIT({
+    g_allocator.deallocate(non_existing_path, g_allocator.state);
+  });
+}
+
+TEST_F(TestFilesystemFixture, calculate_file_size) {
+  char * path =
+    rcutils_join_path(this->test_path, "dummy_readable_file.txt", g_allocator);
+  size_t size = rcutils_get_file_size(path);
+  OSRF_TESTING_TOOLS_CPP_SCOPE_EXIT({
+    g_allocator.deallocate(path, g_allocator.state);
+  });
+  ASSERT_EQ(5u, size);
+
+  char * non_existing_path =
+    rcutils_join_path(this->test_path, "non_existing_file.txt", g_allocator);
+  size = rcutils_get_file_size(non_existing_path);
+  ASSERT_EQ(0u, size);
+  OSRF_TESTING_TOOLS_CPP_SCOPE_EXIT({
+    g_allocator.deallocate(non_existing_path, g_allocator.state);
+  });
+}