dj(1): add a ton of assertions, fix if statement, fix io[i] mixups

This commit is contained in:
dtb 2024-07-03 14:22:23 -06:00
parent 064abb82a6
commit 1cf67af281
Signed by: trinity
GPG Key ID: 34C0543BBB6AF81B

View File

@ -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 */
@ -68,7 +69,9 @@ 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.
@ -76,6 +79,8 @@ Io_bufalloc(struct Io *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));
@ -118,6 +127,8 @@ 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))
@ -135,7 +146,14 @@ Io_fdopen(struct Io *io, char *fn){
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;
@ -309,12 +328,13 @@ 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 */
Io_read(&io[0]);