Merge pull request #22 from evelikov/zstd-followups

Follow-up zstd fixes

meson.build

@@ -11,6 +11,7 @@ project('tqftpserv',
 prefix = get_option('prefix')
 
 zstd_dep = dependency('libzstd')
+add_project_arguments('-DHAVE_ZSTD', language : 'c')
 
 # Not required to build the executable, only to install unit file
 systemd = dependency('systemd', required : false)

tqftpserv.c

@@ -15,7 +15,6 @@
 
 #include "list.h"
 #include "translate.h"
-#include "zstd-decompress.h"
 
 #define MAX(x, y) ((x) > (y) ? (x) : (y))
 
@@ -571,8 +570,6 @@ int main(int argc, char **argv)
 		exit(1);
 	}
 
-	zstd_init();
-
 	for (;;) {
 		FD_ZERO(&rfds);
 		FD_SET(fd, &rfds);
@@ -674,7 +671,6 @@ int main(int argc, char **argv)
 	}
 
 	close(fd);
-	zstd_free();
 
 	return 0;
 }

zstd-decompress.c

@@ -1,6 +1,7 @@
 // SPDX-License-Identifier: BSD-3-Clause
 /*
  * Copyright (c) 2024, Stefan Hansson
+ * Copyright (c) 2024, Emil Velikov
  */
 
 /* For memfd_create */
@@ -17,24 +18,6 @@
 
 #include "zstd-decompress.h"
 
-static ZSTD_DCtx *zstd_context = NULL;
-
-/**
- * zstd_init() - set up state for decompression. Needs to be called before zstd_decompress_file()
- */
-void zstd_init()
-{
-	zstd_context = ZSTD_createDCtx();
-}
-
-/**
- * zstd_free() - free state used for decompression. zstd_decompress_file() may not be called after this
- */
-void zstd_free()
-{
-	ZSTD_freeDCtx(zstd_context);
-}
-
 /**
  * zstd_decompress_file() - decompress a zstd-compressed file
  * @filename:	path to a file to decompress
@@ -52,7 +35,7 @@ int zstd_decompress_file(const char *filename)
 
 	const size_t file_size = file_stat.st_size;
 
-	const int input_file_fd = open(filename, 0);
+	const int input_file_fd = open(filename, O_RDONLY);
 	if (input_file_fd == -1) {
 		perror("open failed");
 		return -1;
@@ -69,34 +52,43 @@ int zstd_decompress_file(const char *filename)
 	const unsigned long long decompressed_size = ZSTD_getFrameContentSize(compressed_buffer, file_size);
 	if (decompressed_size == ZSTD_CONTENTSIZE_UNKNOWN) {
 		fprintf(stderr, "Content size could not be determined for %s\n", filename);
+		munmap(compressed_buffer, file_size);
 		return -1;
 	}
 	if (decompressed_size == ZSTD_CONTENTSIZE_ERROR) {
 		fprintf(stderr, "Error getting content size for %s\n", filename);
+		munmap(compressed_buffer, file_size);
 		return -1;
 	}
 
 	void* const decompressed_buffer = malloc((size_t)decompressed_size);
 	if (decompressed_buffer == NULL) {
 		perror("malloc failed");
+		munmap(compressed_buffer, file_size);
 		return -1;
 	}
 
-	const size_t return_size = ZSTD_decompressDCtx(zstd_context, decompressed_buffer, decompressed_size, compressed_buffer, file_size);
+	const size_t return_size = ZSTD_decompress(decompressed_buffer, decompressed_size, compressed_buffer, file_size);
 	if (ZSTD_isError(return_size)) {
 		fprintf(stderr, "ZSTD_decompress failed: %s\n", ZSTD_getErrorName(return_size));
+		free(decompressed_buffer);
+		munmap(compressed_buffer, file_size);
 		return -1;
 	}
 
 	const int output_file_fd = memfd_create(filename, 0);
 	if (output_file_fd == -1) {
 		perror("memfd_create failed");
+		free(decompressed_buffer);
+		munmap(compressed_buffer, file_size);
 		return -1;
 	}
 
 	if (write(output_file_fd, decompressed_buffer, decompressed_size) != decompressed_size) {
 		perror("write failed");
 		close(output_file_fd);
+		free(decompressed_buffer);
+		munmap(compressed_buffer, file_size);
 		return -1;
 	}
 

zstd-decompress.h

@@ -8,8 +8,14 @@
 
 #include <stdbool.h>
 
-void zstd_init();
-void zstd_free();
+#ifdef HAVE_ZSTD
 int zstd_decompress_file(const char *filename);
+#else
+static int zstd_decompress_file(const char *filename)
+{
+	fprintf(stderr, "Built without ZSTD support\n");
+	return -1;
+}
+#endif
 
 #endif