Merge branch 'main' into dj

src/dj.c

@@ -37,16 +37,17 @@ char *program_name = "dj";
  * writing ends of its jockeyed "pipe". User-configurable members are noted
  * with their relevant options. */
 struct Io{
-	int bs;       	/* buffer size (-bB) */
-	size_t bufuse;	/* buffer usage */
 	char *buf;	  	/* buffer */
+	char *fn;	  	/* file name (-io) */
+	size_t bs;    	/* buffer size (-bB) */
+	size_t bufuse;	/* buffer usage */
 	size_t bytes; 	/* bytes processed */
-	int fd;			/* file descriptor */
-	int fl;			/* file opening flags */
-	char *fn;		/* file name (may be stdin_name or stdout_name) (-io) */
 	size_t prec;  	/* partial records processed */
 	size_t rec;   	/* records processed */
-	long seek;		/* bytes to seek/skip (will be 0 after skippage) (-sS) */
+	long seek;  	/* remaining bytes to seek/skip (-sS) */
+	int error;  	/* errno */
+	int fd;		  	/* file descriptor */
+	int fl;		  	/* file opening flags */
 };
 
 /* To be assigned to main:fmt and used with printio(). */
@@ -73,15 +74,18 @@ Io_read(struct Io *io){
 	assert(io->bs > 0);
 	assert(io->bufuse < io->bs);
 
-	io->bufuse += (t = read(io->fd, &(io->buf)[io->bufuse],
-		io->bs - io->bufuse));
-
-	assert(io->bufuse <= io->bs);
+	if((t = read(io->fd, &(io->buf)[io->bufuse], io->bs - io->bufuse)) < 0){
+		io->error = errno;
+		t = 0;
+	}
 
+	io->bufuse += t;
 	io->bytes  += t;
 	io->prec   += (0 < io->bufuse && io->bufuse < io->bs);
 	io->rec    += (io->bufuse == io->bs);
 
+	assert(io->bufuse <= io->bs);
+
 	return io;
 }
 
@@ -92,23 +96,22 @@ Io_write(struct Io *io){
 	assert(io->bufuse > 0);
 	assert(io->bufuse <= io->bs);
 
-	if((t = write(io->fd, io->buf, io->bufuse)) > 0)
+	if((t = write(io->fd, io->buf, io->bufuse)) < 0){
+		io->error = errno;
+		t = 0;
+	}else if(t > 0)
 		memmove(io->buf, &(io->buf)[t], (io->bufuse -= t));
 
 	io->bytes += t;
-	io->prec  += (0 < io->bufuse && 0 < t);
-	io->rec   += (io->bufuse == 0 && 0 < t);
+	io->prec  += (t > 0 && io->bufuse > 0);
+	io->rec   += (t > 0 && io->bufuse == 0);
 
 	return io;
 }
 
-/* Prints an error message suitable for the event of an operating system error,
- * with the error itself to be described in the string s. */
 static int
-oserr(char *s){
-
-	fprintf(stderr, "%s: %s: %s\n", program_name, s, strerror(errno));
-
+oserr(char *e, int n){
+	fprintf(stderr, "%s: %s: %s\n", program_name, e, strerror(n));
 	return EX_OSERR;
 }
 
@@ -155,20 +158,21 @@ int main(int argc, char *argv[]){
 	char *fmt;    /* == fmt_asv (default) or fmt_human (-H) */
 	size_t i;     /* side of io being modified */
 	char noerror; /* 0=exits (default) 1=retries on partial reads or writes */
-	struct Io io[2];
+	struct Io io[2 /* { in, out } */];
 
 	/* Set defaults. */
 	align = -1;
 	count = 0;
 	fmt = fmt_asv;
 	noerror = 0;
-	for(i = 0; i < 2; ++i){
+	for(i = 0; i < (sizeof io) / (sizeof *io); ++i){
 		io[i].bs = 1024 /* 1 KiB */; /* GNU dd(1) default; POSIX says 512B */
 		io[i].bufuse = 0;
 		io[i].bytes = 0;
 		io[i].fd = i == 0 ? STDIN_FILENO : STDOUT_FILENO;
 		io[i].fn = i == 0 ? stdin_name   : stdout_name;
 		io[i].fl = i == 0 ? read_flags   : write_flags;
+		io[i].error = 0;
 		io[i].prec = 0;
 		io[i].rec = 0;
 		io[i].seek = 0;
@@ -195,7 +199,7 @@ int main(int argc, char *argv[]){
 						break;
 					}
 				}
-				return oserr(optarg);
+				return oserr(optarg, errno);
 			case 'n': noerror = 1;     break;
 			case 'H': fmt = fmt_human; break;
 			case 'a':
@@ -224,10 +228,10 @@ int main(int argc, char *argv[]){
 	if(argc > optind)
 		return usage(program_name);
 
-	for(i = 0; i < 2; ++i){
+	for(i = 0; i < (sizeof io) / (sizeof *io); ++i){
 		/* buffer allocation */
 		if((io[i].buf = malloc(io[i].bs * (sizeof *(io[i].buf)))) == NULL){
-			fprintf(stderr, "%s: Failed to allocate %d bytes\n",
+			fprintf(stderr, "%s: Failed to allocate %zd bytes\n",
 				program_name, io[i].bs);
 			return EX_OSERR;
 		}
@@ -242,15 +246,17 @@ int main(int argc, char *argv[]){
 		do{
 			memset(io[1].buf, '\0',
 				(t = io[1].bufuse = MIN(io[1].bs, io[1].seek)));
-			if(Io_write(&io[1])->bufuse == t && !noerror)
+			if(Io_write(&io[1])->bufuse == t && !noerror && io[1].error == 0)
 				Io_write(&io[1]); /* second chance */
+			if(io[1].error != 0)
+				return oserr(io[1].fn, io[1].error);
 		}while((io[1].seek -= (t - io[1].bufuse)) > 0 && io[1].bufuse != t);
 		io[1].bufuse = 0;
 	}
 
 	if(io[1].seek > 0){
 		fprintio(stderr, fmt, io);
-		return oserr(io[1].fn);
+		return oserr(io[1].fn, errno);
 	}
 
 	do{
@@ -258,20 +264,20 @@ int main(int argc, char *argv[]){
 
 		{ /* read */
 			char skipping;
-			int t;
+			size_t t;
 
+			/* hack to intentionally get a partial read from Io_read */
 			if((skipping = (io[0].seek > 0)) && io[0].seek < io[0].bs)
 				io[0].bufuse = io[0].bs - io[0].seek;
 
 			t = io[0].bufuse;
-			if(Io_read(&io[0])->bufuse == t && !noerror)
+			if(Io_read(&io[0])->bufuse == t && !noerror && io[0].error == 0)
 				Io_read(&io[0]); /* second chance */
+			assert(io[0].bufuse >= t);
 			if(io[0].bufuse == t) /* that's all she wrote */
 				break;
 
 			if(/* t < io[0].bufuse && */ io[0].bufuse < io[0].bs){
-				assert(!skipping);
-
 				fprintf(stderr, "%s: Partial read:\n\t", program_name);
 				fprintio(stderr, fmt, io);
 				if(!noerror)
@@ -319,8 +325,9 @@ int main(int argc, char *argv[]){
 			}
 
 			t = io[1].bufuse;
-			if(Io_write(&io[1])->bufuse == t && !noerror)
+			if(Io_write(&io[1])->bufuse == t && !noerror && io[1].error == 0)
 				Io_write(&io[1]); /* second chance */
+			assert(io[1].bufuse <= t);
 			if(io[1].bufuse == t){ /* no more love */
 				count = 1;
 				break;
@@ -337,5 +344,9 @@ int main(int argc, char *argv[]){
 
 	fprintio(stderr, fmt, io);
 
+	for(i = 0; i < (sizeof io) / (sizeof *io); ++i)
+		if(io[i].error)
+			return oserr(io[i].fn, io[i].error);
+
 	return EX_OK;
 }

src/swab.rs

@@ -29,8 +29,11 @@ use getopt::GetOpt;
 extern crate sysexits;
 use sysexits::{ EX_OK, EX_OSERR, EX_USAGE };
 
+extern crate strerror;
+use strerror::StrError;
+
 fn oserr(s: &str, e: Error) -> ExitCode {
-	eprintln!("{}: {}", s, e);
+	eprintln!("{}: {}", s, e.strerror());
 	ExitCode::from(EX_OSERR as u8)
 }