When dumping the DMI table to a binary file, truncate the file first.

3 files changed, 6 insertions, 8 deletions

diff --git a/dmidecode.c b/dmidecode.c
index b85ef06..c0a2399 100644
--- a/dmidecode.c
+++ b/dmidecode.c
@@ -3802,7 +3802,7 @@ static void dmi_table_dump(u32 base, u16 len, const char *devmem)
 	}
 
 	printf("# Writing %d bytes to %s.\n", len, opt.dumpfile);
-	write_dump(32, len, buf, opt.dumpfile);
+	write_dump(32, len, buf, opt.dumpfile, 0);
 	free(buf);
 }
 
@@ -3967,7 +3967,7 @@ static int smbios_decode(u8 *buf, const char *devmem)
 		overwrite_dmi_address(crafted + 0x10);
 
 		printf("# Writing %d bytes to %s.\n", crafted[0x05], opt.dumpfile);
-		write_dump(0, crafted[0x05], crafted, opt.dumpfile);
+		write_dump(0, crafted[0x05], crafted, opt.dumpfile, 1);
 	}
 
 	return 1;
@@ -3993,7 +3993,7 @@ static int legacy_decode(u8 *buf, const char *devmem)
 		overwrite_dmi_address(crafted);
 
 		printf("# Writing %d bytes to %s.\n", 0x0F, opt.dumpfile);
-		write_dump(0, 0x0F, crafted, opt.dumpfile);
+		write_dump(0, 0x0F, crafted, opt.dumpfile, 1);
 	}
 
 	return 1;
diff --git a/util.c b/util.c
index dfdc028..15d24a7 100644
--- a/util.c
+++ b/util.c
@@ -164,13 +164,11 @@ void *mem_chunk(size_t base, size_t len, const char *devmem)
 	return p;
 }
 
-int write_dump(size_t base, size_t len, const void *data, const char *dumpfile)
+int write_dump(size_t base, size_t len, const void *data, const char *dumpfile, int add)
 {
 	FILE *f;
 
-	f=fopen(dumpfile, "r+b");
-	if (!f && errno == ENOENT)
-		f = fopen(dumpfile, "wb");
+	f = fopen(dumpfile, add ? "r+b" : "wb");
 	if (!f)
 	{
 		fprintf(stderr, "%s: ", dumpfile);
diff --git a/util.h b/util.h
index 98b49c6..894bd2f 100644
--- a/util.h
+++ b/util.h
@@ -26,4 +26,4 @@
 
 int checksum(const u8 *buf, size_t len);
 void *mem_chunk(size_t base, size_t len, const char *devmem);
-int write_dump(size_t base, size_t len, const void *data, const char *dumpfile);
+int write_dump(size_t base, size_t len, const void *data, const char *dumpfile, int add);