dj(1): add a ton of assertions, fix if statement, fix io[i] mixups
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							| @ -16,6 +16,7 @@ | ||||
|  * along with this program. If not, see https://www.gnu.org/licenses/.
 | ||||
|  */ | ||||
| 
 | ||||
| #include <assert.h> /* assert(3) */ | ||||
| #include <errno.h> /* errno */ | ||||
| #include <fcntl.h> /* open(2) */ | ||||
| #include <stdio.h> /* fprintf(3), stderr */ | ||||
| @ -68,14 +69,18 @@ static int write_flags = O_WRONLY | O_CREAT; | ||||
| static void * | ||||
| Io_bufalloc(struct Io *io){ | ||||
| 
 | ||||
| 	return (io->buf = malloc(io->bs * (sizeof *io->buf))); | ||||
| 	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 * | ||||
| Io_bufrpad(struct Io *io, int padding){ | ||||
| 	 | ||||
| 
 | ||||
| 	assert(io != NULL); | ||||
| 
 | ||||
| 	memset(io->buf + io->bufuse, padding, io->bs - io->bufuse); | ||||
| 	io->bufuse = io->bs; | ||||
| 
 | ||||
| @ -90,6 +95,8 @@ static struct Io* | ||||
| Io_bufxapp(struct Io *dest, struct Io *src){ | ||||
| 	int n; | ||||
| 
 | ||||
| 	assert(dest != NULL && src != NULL); | ||||
| 
 | ||||
| 	n = MIN(src->bufuse, dest->bs - dest->bufuse); | ||||
| 	memcpy(dest->buf + dest->bufuse, src->buf, n); | ||||
| 	dest->bufuse += n; | ||||
| @ -106,6 +113,8 @@ Io_bufxapp(struct Io *dest, struct Io *src){ | ||||
| static struct Io* | ||||
| Io_bufxfer(struct Io *dest, struct Io *src, int n){ | ||||
| 
 | ||||
| 	assert(dest != NULL && src != NULL); | ||||
| 
 | ||||
| 	memcpy(dest->buf, src->buf, (dest->bufuse = n)); | ||||
| 	memmove(src->buf, src->buf + n, (src->bufuse -= n)); | ||||
| 
 | ||||
| @ -117,7 +126,9 @@ Io_bufxfer(struct Io *dest, struct Io *src, int n){ | ||||
| static int | ||||
| Io_fdopen(struct Io *io, char *fn){ | ||||
| 	int fd; | ||||
| 	 | ||||
| 
 | ||||
| 	assert(io != NULL); | ||||
| 
 | ||||
| 	if((fd = open(fn, io->fl, | ||||
| 					/* these are the flags used by touch(1p) */ | ||||
| 					S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP | S_IROTH | S_IWOTH)) | ||||
| @ -134,8 +145,15 @@ Io_fdopen(struct Io *io, char *fn){ | ||||
|  * of sought bytes from io->seek. This procedure leaves garbage in io->buf. */ | ||||
| static void | ||||
| Io_fdseek(struct Io *io){ | ||||
| 	 | ||||
| 	if(io->seek != 0 | ||||
| 
 | ||||
| 	assert(io != NULL); | ||||
| 	assert(io->fd != STDIN_FILENO  || io->fl == read_flags); | ||||
| 	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; | ||||
| 
 | ||||
| @ -160,7 +178,8 @@ Io_fdseek(struct Io *io){ | ||||
| 				/* second chance */ | ||||
| 				io->bufuse = read(io->fd, io->buf, MIN(io->bs, io->seek)); | ||||
| 		}while((io->seek -= io->bufuse) > 0 && io->bufuse != 0); | ||||
| 	} | ||||
| 	}else | ||||
| 		assert(0); /* UNREACHABLE */ | ||||
| 
 | ||||
| 	io->bufuse = 0; | ||||
| 
 | ||||
| @ -255,9 +274,9 @@ int main(int argc, char *argv[]){ | ||||
| 	for(i = 0; i < 2; ++i){ | ||||
| 		io[i].bs = 1024 /* 1 KiB */; /* GNU dd(1) default; POSIX says 512B */ | ||||
| 		io[i].bytes = 0; | ||||
| 		io[i].fd = i ? STDIN_FILENO : STDOUT_FILENO; | ||||
| 		io[i].fn = i ? stdin_name   : stdout_name; | ||||
| 		io[i].fl = i ? read_flags   : write_flags; | ||||
| 		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].prec = 0; | ||||
| 		io[i].rec = 0; | ||||
| 		io[i].seek = 0; | ||||
| @ -271,8 +290,8 @@ int main(int argc, char *argv[]){ | ||||
| 			switch(c){ | ||||
| 			case 'i': case 'o': i = (c == 'o'); | ||||
| 				if(optarg[0] == '-' && optarg[1] == '\0'){ /* optarg == "-" */ | ||||
| 					io[i].fd = i ? STDIN_FILENO : STDOUT_FILENO; | ||||
| 					io[i].fn = i ? stdin_name   : stdout_name; | ||||
| 					io[i].fd = i == 0 ? STDIN_FILENO : STDOUT_FILENO; | ||||
| 					io[i].fn = i == 0 ? stdin_name   : stdout_name; | ||||
| 					break; | ||||
| 				}else if(Io_fdopen(&io[i], optarg) != -1) | ||||
| 					break; | ||||
| @ -309,11 +328,12 @@ int main(int argc, char *argv[]){ | ||||
| 			fprintf(stderr, "%s: Failed to allocate %d bytes\n", | ||||
| 				program_name, io[i].bs); | ||||
| 			return EX_OSERR; | ||||
| 		}else if(io[i].seek > 0) | ||||
| 		}else if(io[i].seek > 0){ | ||||
| 			Io_fdseek(&io[i]); | ||||
| 			if(io[i].seek > 0){ | ||||
| 				return oserr(io[i].fn); | ||||
| 			} | ||||
| 		} | ||||
| 	} | ||||
| 
 | ||||
| 	do{	/* read */ | ||||
|  | ||||
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