src/dj.c

@@ -47,7 +47,7 @@ struct Io{
 	long seek;		/* bytes to seek/skip (will be 0 after skippage) (-sS) */
 }; 
 
-/* To be assigned to main:fmt and used with printio(). */
+/* To be assigned to main:fmt_output and used with output(). */
 static char *fmt_asv   = "%d\037%d\036%d\037%d\035%d\036%d\034";
 static char *fmt_human = "%d+%d > %d+%d; %d > %d\n";
 
@@ -65,6 +65,15 @@ static int write_flags = O_WRONLY | O_CREAT;
 		|| (fd) == STDOUT_FILENO \
 		|| (fd) == STDERR_FILENO)
 
+/* Allocates *io's buffer. Returns NULL if unsuccessful. */
+static void *
+Io_bufalloc(struct Io *io){
+
+	return io != NULL
+		? (io->buf = malloc(io->bs * (sizeof *io->buf)))
+		: NULL;
+}
+
 /* Fills the unused portion of io's buffer with padding, updating io->bufuse.
  * Returns io. */
 static struct Io *
@@ -142,6 +151,8 @@ Io_fdseek(struct Io *io){
 	assert(io->fd != STDOUT_FILENO || io->fl == write_flags);
 	assert(io->fd != STDERR_FILENO || io->fl == write_flags);
 
+	printf("%s\n", io->fn);
+
 	if(io->seek == 0
 			|| (!fdisstd(io->fd) && lseek(io->fd, io->seek, SEEK_SET) != -1))
 		return;
@@ -213,7 +224,7 @@ oserr(char *s){
 /* Prints statistics regarding the use of dj, particularly partially and
  * completely read and written records. */
 static void
-printio(char *fmt, struct Io io[2]){
+output(struct Io io[2], char *fmt){
 
 	fprintf(stderr, fmt,
 		io[0].rec, io[0].prec, io[1].rec, io[1].prec,
@@ -250,7 +261,7 @@ usage(char *s){
 int main(int argc, char *argv[]){
 	int align; /* low 8b used, negative if no alignment is being done */
 	int count; /* 0 if dj(1) runs until no more reads are possible */
-	char *fmt; /* == fmt_asv (default) or fmt_human (-H) */
+	char *fmt_output; /* == fmt_asv (default) or fmt_human (-H) */
 	size_t i; /* side of io being modified */
 	struct Io io[2];
 	char noerror; /* 0=exits (default) 1=retries on partial reads or writes */
@@ -258,7 +269,7 @@ int main(int argc, char *argv[]){
 	/* Set defaults. */
 	align = -1;
 	count = 0;
-	fmt = fmt_asv;
+	fmt_output = fmt_asv;
 	noerror = 0;
 	for(i = 0; i < 2; ++i){
 		io[i].bs = 1024 /* 1 KiB */; /* GNU dd(1) default; POSIX says 512B */
@@ -286,7 +297,7 @@ int main(int argc, char *argv[]){
 					break;
 				return oserr(optarg);
 			case 'n': noerror = 1; break;
-			case 'H': fmt = fmt_human; break;
+			case 'H': fmt_output = fmt_human; break;
 			case 'a':
 				if(optarg[0] == '\0' || optarg[1] == '\0'){
 					align = optarg[0];
@@ -296,7 +307,7 @@ int main(int argc, char *argv[]){
 			case 'c': case 'b': case 's': case 'B': case 'S': /* numbers */
 				if(c == 'c' && (count = parse(optarg)) >= 0)
 					break;
-				i = (c >= 'A' && c <= 'Z');
+				i = (c >= 'A' && c <= 'Z'); /* uppercase changes output */
 				c |= 0x20 /* 0b 0010 0000 */; /* (ASCII) make lowercase */
 				if((c == 'b' && (io[i].bs = parse(optarg)) > 0)
 						|| (c == 's' && (io[i].seek = parse(optarg)) >= 0))
@@ -313,7 +324,7 @@ int main(int argc, char *argv[]){
 	}
 
 	for(i = 0; i < 2; ++i){
-		if((io[i].buf = malloc(io[i].bs * (sizeof *(io[i].buf)))) == NULL){
+		if(Io_bufalloc(&io[i]) == NULL){
 			fprintf(stderr, "%s: Failed to allocate %d bytes\n",
 				program_name, io[i].bs);
 			return EX_OSERR;
@@ -334,7 +345,7 @@ int main(int argc, char *argv[]){
 		else if(io[0].bufuse < io[0].bs){
 			++io[0].prec;
 			fprintf(stderr, "%s: Partial read:\n\t", program_name);
-			printio(fmt, io);
+			output(io, fmt_output);
 			if(!noerror)
 				count = 1;
 			if(align >= 0)
@@ -363,7 +374,7 @@ int main(int argc, char *argv[]){
 			}else if(t > io[1].bufuse && io[1].bufuse > 0){
 				io[1].prec += 1;
 				fprintf(stderr, "%s: Partial write:\n\t", program_name);
-				printio(fmt, io);
+				output(io, fmt_output);
 				if(!noerror)
 					count = 1;
 			}else if(io[1].bufuse == 0 && t < io[1].bs)
@@ -373,7 +384,7 @@ int main(int argc, char *argv[]){
 		}while(io[0].bufuse > 0);
 	}while(count == 0 || --count > 0);
 
-	printio(fmt, io);
+	output(io, fmt_output);
 
 	return EX_OK;
 }