util/ifdtool: add --output flag

Add an optional commandline flag to define the filename of the resulting
output file. If this flag is not defined, it will behave like before by
using the old filename with a ".new" suffix.

With this additional flag it is not necessary to move the output file at
build-time, and the stdout print "Writing new image to <filename>" makes
more sense in the build context.

Change-Id: I824e94e93749f55c3576e4ee2f7804d855fefed2
Signed-off-by: Marcello Sylvester Bauer <sylv@sylv.io>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/38828
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Patrick Rudolph <siro@das-labor.org>

util/ifdtool/ifdtool.c

@@ -854,17 +854,11 @@ static void validate_layout(char *image, int size)
 
 static void write_image(const char *filename, char *image, int size)
 {
-	char new_filename[FILENAME_MAX]; // allow long file names
 	int new_fd;
-
+	printf("Writing new image to %s\n", filename);
-	// - 5: leave room for ".new\0"
-	strncpy(new_filename, filename, FILENAME_MAX - 5);
-	strncat(new_filename, ".new", FILENAME_MAX - strlen(filename));
-
-	printf("Writing new image to %s\n", new_filename);
 
 	// Now write out new image
-	new_fd = open(new_filename,
+	new_fd = open(filename,
 			 O_WRONLY | O_CREAT | O_TRUNC | O_BINARY,
 			 S_IRUSR | S_IWUSR | S_IRGRP | S_IROTH);
 	if (new_fd < 0) {
@@ -1429,6 +1423,7 @@ static void print_usage(const char *name)
 	       "   -x | --extract:                       extract intel fd modules\n"
 	       "   -i | --inject <region>:<module>       inject file <module> into region <region>\n"
 	       "   -n | --newlayout <filename>           update regions using a flashrom layout file\n"
+	       "   -O | --output <filename>              output filename\n"
 	       "   -s | --spifreq <17|20|30|33|48|50>    set the SPI frequency\n"
 	       "   -D | --density <512|1|2|4|8|16|32|64> set chip density (512 in KByte, others in MByte)\n"
 	       "   -C | --chip <0|1|2>                   select spi chip on which to operate\n"
@@ -1460,6 +1455,7 @@ int main(int argc, char *argv[])
 	int mode_altmedisable = 0, altmedisable = 0;
 	char *region_type_string = NULL, *region_fname = NULL;
 	const char *layout_fname = NULL;
+	char *new_filename = NULL;
 	int region_type = -1, inputfreq = 0;
 	unsigned int new_density = 0;
 	enum spi_frequency spifreq = SPI_FREQUENCY_20MHZ;
@@ -1470,6 +1466,7 @@ int main(int argc, char *argv[])
 		{"extract", 0, NULL, 'x'},
 		{"inject", 1, NULL, 'i'},
 		{"newlayout", 1, NULL, 'n'},
+		{"output", 1, NULL, 'O'},
 		{"spifreq", 1, NULL, 's'},
 		{"density", 1, NULL, 'D'},
 		{"chip", 1, NULL, 'C'},
@@ -1484,7 +1481,7 @@ int main(int argc, char *argv[])
 		{0, 0, 0, 0}
 	};
 
-	while ((opt = getopt_long(argc, argv, "df:D:C:M:xi:n:s:p:eluvth?",
+	while ((opt = getopt_long(argc, argv, "df:D:C:M:xi:n:O:s:p:eluvth?",
 				  long_options, &option_index)) != EOF) {
 		switch (opt) {
 		case 'd':
@@ -1543,6 +1540,14 @@ int main(int argc, char *argv[])
 				exit(EXIT_FAILURE);
 			}
 			break;
+		case 'O':
+			new_filename = strdup(optarg);
+			if (!new_filename) {
+				fprintf(stderr, "No output filename specified\n");
+				print_usage(argv[0]);
+				exit(EXIT_FAILURE);
+			}
+			break;
 		case 'D':
 			mode_density = 1;
 			new_density = strtoul(optarg, NULL, 0);
@@ -1731,6 +1736,18 @@ int main(int argc, char *argv[])
 
 	close(bios_fd);
 
+	// generate new filename
+	if (new_filename == NULL) {
+		new_filename = (char *) malloc((strlen(filename) + 5) * sizeof(char));
+		if (!new_filename) {
+			printf("Out of memory.\n");
+			exit(EXIT_FAILURE);
+		}
+		// - 5: leave room for ".new\0"
+		strcpy(new_filename, filename);
+		strcat(new_filename, ".new");
+	}
+
 	check_ifd_version(image, size);
 
 	if (mode_dump)
@@ -1746,34 +1763,35 @@ int main(int argc, char *argv[])
 		validate_layout(image, size);
 
 	if (mode_inject)
-		inject_region(filename, image, size, region_type,
+		inject_region(new_filename, image, size, region_type,
 				region_fname);
 
 	if (mode_newlayout)
-		new_layout(filename, image, size, layout_fname);
+		new_layout(new_filename, image, size, layout_fname);
 
 	if (mode_spifreq)
-		set_spi_frequency(filename, image, size, spifreq);
+		set_spi_frequency(new_filename, image, size, spifreq);
 
 	if (mode_density)
-		set_chipdensity(filename, image, size, new_density);
+		set_chipdensity(new_filename, image, size, new_density);
 
 	if (mode_em100)
-		set_em100_mode(filename, image, size);
+		set_em100_mode(new_filename, image, size);
 
 	if (mode_locked)
-		lock_descriptor(filename, image, size);
+		lock_descriptor(new_filename, image, size);
 
 	if (mode_unlocked)
-		unlock_descriptor(filename, image, size);
+		unlock_descriptor(new_filename, image, size);
 
 	if (mode_altmedisable) {
 		fpsba_t *fpsba = find_fpsba(image, size);
 		fmsba_t *fmsba = find_fmsba(image, size);
 		fpsba_set_altmedisable(fpsba, fmsba, altmedisable);
-		write_image(filename, image, size);
+		write_image(new_filename, image, size);
 	}
 
+	free(new_filename);
 	free(image);
 
 	return 0;