From 214abeb18154066b1aee6dcc3edd172ea679a654 Mon Sep 17 00:00:00 2001
From: Intel A80486DX2-66 <larry.holst@disroot.org>
Date: Mon, 23 Sep 2024 00:43:25 +0300
Subject: [PATCH] C: fix file I/O code

---
 src/template.c | 44 +++++++++++++++++++++++++++++++++++++++-----
 1 file changed, 39 insertions(+), 5 deletions(-)

diff --git a/src/template.c b/src/template.c
index 19b6d3d..8237fa6 100644
--- a/src/template.c
+++ b/src/template.c
@@ -9,6 +9,38 @@
 
 #include "`fwrite_le`"
 
+#if _FILE_OFFSET_BITS == 64 || _POSIX_C_SOURCE >= 200112L
+ # define FSEEK_MACRO fseeko
+ # define FSEEK_FUNCTION_NAME "fseeko"
+typedef off_t file_offset_t;
+#else
+ # define FSEEK_MACRO fseek
+ # define FSEEK_FUNCTION_NAME "fseek"
+typedef int file_offset_t;
+#endif
+
+#define STRINGIZE(x) #x
+
+#define FILE_IO_NO_FAIL(function, ptr, size, nitems, stream) do {             \
+    if (function(ptr, size, nitems, stream) != nitems) {                      \
+        /* clean up */                                                        \
+        free(buffer);                                                         \
+                                                                              \
+        perror(STRINGIZE(function));                                          \
+        exit(EXIT_FAILURE);                                                   \
+    }                                                                         \
+} while (0)
+
+#define FSEEK_NO_FAIL(...) do {                                               \
+    if (FSEEK_MACRO(__VA_ARGS__) == -1) {                                     \
+        perror(FSEEK_FUNCTION_NAME);                                          \
+        exit(EXIT_FAILURE);                                                   \
+    }                                                                         \
+} while (0)
+
+#define FREAD_NO_FAIL(...) FILE_IO_NO_FAIL(fread, __VA_ARGS__)
+#define FWRITE_NO_FAIL(...) FILE_IO_NO_FAIL(fwrite, __VA_ARGS__)
+
 // typedefs
 typedef uintmax_t bb_counter_t;
 typedef long double bb_fp_return_t;
@@ -418,7 +450,7 @@ main(void)
 
 	for (size_t counter = 0; counter < REPEAT_TIMES; counter++) {
 # if SEQUENTIAL_MODE
-		off_t position_read = header_size;
+		file_offset_t position_read = header_size;
 
 		calc_block_size = BLOCK_SIZE;
 		for (size_t seq = 0, time = 0; seq < MAX; seq++, time += BLOCK_SIZE) {
@@ -428,10 +460,12 @@ main(void)
 				end = true;
 			}
 
-			fseeko(output_file, position_read, SEEK_SET);
-			fread(buffer, sizeof(SAMPLE_TYPE), calc_block_size, output_file);
-			fseeko(output_file, 0, SEEK_END);
-			fwrite(buffer, sizeof(SAMPLE_TYPE), calc_block_size, output_file);
+			FSEEK_NO_FAIL(output_file, position_read, SEEK_SET);
+			FREAD_NO_FAIL(buffer, sizeof(SAMPLE_TYPE), calc_block_size,
+			              output_file);
+			FSEEK_NO_FAIL(output_file, 0, SEEK_END);
+			FWRITE_NO_FAIL(buffer, sizeof(SAMPLE_TYPE), calc_block_size,
+			               output_file);
 
 			if (end)
 				break;