Implement POSIX file IO

src/os/file/posix/file_posix.c

@@ -0,0 +1,180 @@
+// vim:fileencoding=utf-8:foldmethod=marker
+
+#include "file_posix.h"
+#include "../../../common/platform/platform.h"
+
+#ifdef WAPP_PLATFORM_POSIX
+
+#include "../file.h"
+#include "../../cpath/cpath.h"
+#include "../../../common/aliases/aliases.h"
+#include "../../../base/array/array.h"
+#include "../../../base/strings/str8/str8.h"
+#include <fcntl.h>
+#include <unistd.h>
+#include <sys/types.h>
+
+wapp_intern i32 file_flags[FILE_ACCESS_MODE_COUNT] = {
+	[WAPP_ACCESS_READ]                       = O_RDONLY,
+	[WAPP_ACCESS_WRITE]                      = O_WRONLY | O_CREAT,
+	[WAPP_ACCESS_APPEND]                     = O_WRONLY | O_APPEND | O_CREAT,
+	[WAPP_ACCESS_READ_EX]                    = O_RDWR,
+	[WAPP_ACCESS_WRITE_EX]                   = O_RDWR | O_CREAT,
+	[WAPP_ACCESS_APPEND_EX]                  = O_RDWR | O_APPEND | O_CREAT,
+	[WAPP_ACCESS_READ_BIN]                   = O_RDONLY,
+	[WAPP_ACCESS_WRITE_BIN]                  = O_WRONLY | O_CREAT,
+	[WAPP_ACCESS_APPEND_BIN]                 = O_WRONLY | O_APPEND | O_CREAT,
+	[WAPP_ACCESS_READ_BIN_EX]                = O_RDWR,
+	[WAPP_ACCESS_WRITE_BIN_EX]               = O_RDWR | O_CREAT,
+	[WAPP_ACCESS_APPEND_BIN_EX]              = O_RDWR | O_APPEND | O_CREAT,
+	[WAPP_ACCESS_WRITE_FAIL_ON_EXIST]        = O_WRONLY | O_CREAT | O_EXCL,
+	[WAPP_ACCESS_WRITE_FAIL_ON_EXIST_EX]     = O_RDWR | O_CREAT | O_EXCL,
+	[WAPP_ACCESS_WRITE_BIN_FAIL_ON_EXIST]    = O_WRONLY | O_CREAT | O_EXCL,
+	[WAPP_ACCESS_WRITE_BIN_FAIL_ON_EXIST_EX] = O_RDWR | O_CREAT | O_EXCL,
+};
+
+wapp_intern mode_t file_modes[FILE_ACCESS_MODE_COUNT] = {
+	[WAPP_ACCESS_READ]                       = 0,
+	[WAPP_ACCESS_WRITE]                      = S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP,
+	[WAPP_ACCESS_APPEND]                     = S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP,
+	[WAPP_ACCESS_READ_EX]                    = 0,
+	[WAPP_ACCESS_WRITE_EX]                   = S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP,
+	[WAPP_ACCESS_APPEND_EX]                  = S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP,
+	[WAPP_ACCESS_READ_BIN]                   = 0,
+	[WAPP_ACCESS_WRITE_BIN]                  = S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP,
+	[WAPP_ACCESS_APPEND_BIN]                 = S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP,
+	[WAPP_ACCESS_READ_BIN_EX]                = 0,
+	[WAPP_ACCESS_WRITE_BIN_EX]               = S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP,
+	[WAPP_ACCESS_APPEND_BIN_EX]              = S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP,
+	[WAPP_ACCESS_WRITE_FAIL_ON_EXIST]        = S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP,
+	[WAPP_ACCESS_WRITE_FAIL_ON_EXIST_EX]     = S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP,
+	[WAPP_ACCESS_WRITE_BIN_FAIL_ON_EXIST]    = S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP,
+	[WAPP_ACCESS_WRITE_BIN_FAIL_ON_EXIST_EX] = S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP,
+};
+
+wapp_intern i32 file_seek_origins[FILE_SEEK_ORIGIN_COUNT] = {
+	[WAPP_SEEK_START]   = SEEK_SET,
+	[WAPP_SEEK_CURRENT] = SEEK_CUR,
+	[WAPP_SEEK_END]     = SEEK_END,
+};
+
+WFile *_file_open(const Allocator *allocator, Str8RO *filepath, FileAccessMode mode) {
+	wapp_persist c8 tmp[WAPP_PATH_MAX] = {0};
+	memset(tmp, 0, WAPP_PATH_MAX);
+	memcpy(tmp, filepath->buf, filepath->size);
+
+	i32 fd = open((const char *)tmp, file_flags[mode], file_modes[mode]);
+	if (fd < 0) {
+		return NULL;
+	}
+
+	WFile *output = wapp_mem_allocator_alloc(allocator, sizeof(WFile));
+	if (output) {
+		output->fd = fd;
+	}
+
+	return output;
+}
+
+i64 _file_get_current_position(WFile *file) {
+	return lseek64(file->fd, 0, WAPP_SEEK_CURRENT);
+}
+
+i64 _file_seek(WFile *file, i64 offset, FileSeekOrigin origin) {
+	return lseek64(file->fd, offset, file_seek_origins[origin]);
+}
+
+i64 _file_get_length(WFile *file) {
+	i64 current = _file_get_current_position(file);
+
+	_file_seek(file, 0, WAPP_SEEK_END);
+
+	i64 output = _file_get_current_position(file);
+
+	// Restore position
+	_file_seek(file, current, WAPP_SEEK_START);
+
+	return output;
+}
+
+u64 _file_read(void *dst_buf, WFile *file, u64 byte_count) {
+	u64 file_length     = _file_get_length(file);
+	u64 copy_byte_count = file_length <= byte_count ? file_length : byte_count;
+
+	i64 count = read(file->fd, dst_buf, copy_byte_count);
+	if (count < 0) { return 0; }
+
+	return count;
+}
+
+i64 _file_write(const void *src_buf, WFile *file, u64 byte_count) {
+	return write(file->fd, src_buf, byte_count);
+}
+
+u64 _file_read_array(GenericArray dst_buf, WFile *file, u64 item_count) {
+	u64 file_length       = _file_get_length(file);
+	u64 item_size         = wapp_array_item_size(dst_buf);
+	u64 dst_byte_capacity = wapp_array_capacity(dst_buf) * item_size;
+	u64 req_byte_count    = item_count * item_size;
+	u64 copy_byte_count   = 0;
+
+	if (req_byte_count <= file_length && req_byte_count <= dst_byte_capacity) {
+		copy_byte_count = req_byte_count;
+	} else {
+		copy_byte_count = file_length <= dst_byte_capacity ? file_length : dst_byte_capacity;
+	}
+
+	u64 byte_count = _file_read(dst_buf, file, copy_byte_count);
+	if (byte_count == 0) {
+		return 0;
+	}
+
+	wapp_array_set_count(dst_buf, byte_count / item_size);
+
+	return wapp_array_count(dst_buf);
+}
+
+i64 _file_write_array(const GenericArray src_buf, WFile *file, u64 item_count) {
+	u64 item_size      = wapp_array_item_size(src_buf);
+	u64 src_byte_count = wapp_array_count(src_buf) * item_size;
+	u64 req_byte_count = item_count * item_size;
+	u64 to_copy        = req_byte_count <= src_byte_count ? req_byte_count : src_byte_count;
+
+	u64 byte_count = _file_write(src_buf, file, to_copy);
+
+	return byte_count / item_size;
+}
+
+i32 _file_flush(WFile *file) {
+	return fsync(file->fd);
+}
+
+i32 _file_close(WFile *file) {
+	return close(file->fd);
+}
+
+i32 _file_rename(Str8RO *old_filepath, Str8RO *new_filepath) {
+	wapp_persist c8 old_tmp[WAPP_PATH_MAX] = {0};
+	wapp_persist c8 new_tmp[WAPP_PATH_MAX] = {0};
+	memset(old_tmp, 0, WAPP_PATH_MAX);
+	memcpy(old_tmp, old_filepath->buf, old_filepath->size);
+	memset(new_tmp, 0, WAPP_PATH_MAX);
+	memcpy(new_tmp, new_filepath->buf, new_filepath->size);
+
+	i32 link_result = link((const char *)old_tmp, (const char *)new_tmp);
+	if (link_result == 0) {
+		_file_remove(old_filepath);
+	}
+
+	return link_result;
+}
+
+i32 _file_remove(Str8RO *filepath) {
+	wapp_persist c8 tmp[WAPP_PATH_MAX] = {0};
+	memset(tmp, 0, WAPP_PATH_MAX);
+	memcpy(tmp, filepath->buf, filepath->size);
+
+	return unlink((const char *)tmp);
+}
+
+#endif // !WAPP_PLATFORM_POSIX