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now mostly bug free (ignore -o)

This commit is contained in:
dtb 2024-01-06 14:13:39 -07:00
parent 564f7a4381
commit c52dab536e

View File

@ -9,15 +9,15 @@
/* Macro to use the appropriate string for argv[0] in the case that
* argc == 0. */
#define ARGV0 (argv[0] == NULL ? "<no argv[0]>" : argv[0])
#define ARGV0(argv0) ((argv0) == NULL ? program_name : (argv0))
#define MIN(a, b) (((a) < (b)) ? (a) : (b))
/* Macro to ensure fd is not a std* file, e.g. stdin. */
#define fdisnotstd(fd) \
((fd) != STDIN_FILENO \
&& (fd) != STDOUT_FILENO \
&& (fd) != STDERR_FILENO)
/* Macro to check if fd is a std* file, e.g. stdin. */
#define fdisstd(fd) \
((fd) == STDIN_FILENO \
|| (fd) == STDOUT_FILENO \
|| (fd) == STDERR_FILENO)
/* Macro to call the cleanup functions that operate on struct io on the
* particular io[2] used in main. Error conditions are not checked because this
@ -28,29 +28,35 @@
Io_fdclose(&(io)[0]); \
Io_fdclose(&(io)[1]); }while(0)
static int read_flags = O_RDONLY;
static int write_flags = O_WRONLY | O_CREAT;
extern int errno;
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";
static char *fmt_output;
static char *program_name = "<no argv[0]>";
static char *stdin_name = "<stdin>";
static char *stdout_name = "<stdout>";
static int read_flags = O_RDONLY;
static int write_flags = O_WRONLY | O_CREAT;
/* information that needs to be kept about each file in the "pipe" */
struct Io{
int bs; /* buffer size */
size_t bufuse; /* buffer usage */
char *buf; /* buffer */
int bytes; /* bytes processed */
int fd; /* file descriptor */
int fl; /* file opening flags */
char *fn; /* file name (may be stdin_name or stdout_name) */
int prec; /* partial records processed */
int rec; /* records processed */
int seek; /* bytes to seek/skip (will be 0 after skippage) */
long seek; /* bytes to seek/skip (will be 0 after skippage) */
};
/* Allocates *io's buffer. Returns NULL if successful. */
static void *
Io_bufalloc(struct Io *io){
return (io->buf = malloc(io->bs * (sizeof io->buf)));
return (io->buf = malloc(io->bs * (sizeof *io->buf)));
}
/* Frees *io's buffer. Returns io. */
@ -73,6 +79,23 @@ Io_bufrpad(struct Io *io, int padding){
return io;
}
/* Copies from the buffer in src as much as possible to the free space in the
* dest buffer, removing the copied units from src and permuting the remaining
* units in the src buffer to the start of the buffer, modifying both the src
* and dest bufuse and returning dest. */
static struct Io*
Io_bufxapp(struct Io *dest, struct Io *src){
int n;
n = MIN(src->bufuse, dest->bs - dest->bufuse);
memcpy(dest->buf + dest->bufuse, src->buf, n);
dest->bufuse += n;
memmove(src->buf, src->buf + n, src->bs - n);
src->bufuse -= n;
return dest;
}
/* Copies from the buffer in src to the buffer in dest no more than n units,
* removing the copied units from src and permuting the remaining units in the
* src buffer to the start of the buffer, modifying both the src and dest
@ -90,9 +113,9 @@ Io_bufxfer(struct Io *dest, struct Io *src, int n){
static int
Io_fdclose(struct Io *io){
return fdisnotstd(io->fd)
? close(io->fd)
: 0;
return fdisstd(io->fd)
? 0
: close(io->fd);
}
/* Opens io->fn and saves the file descriptor into io->fd. Returns io->fd,
@ -102,7 +125,7 @@ Io_fdopen(struct Io *io, char *fn){
int fd;
if((fd = open(fn, io->fl)) != -1
&& (fdisnotstd(io->fd) || close(io->fd) == 0)){
&& Io_fdclose(io) == 0){
io->fd = fd;
io->fn = fn;
}
@ -111,12 +134,61 @@ Io_fdopen(struct Io *io, char *fn){
}
/* Reads io->bs bytes from *io's file descriptor into io->buf, storing the
* number of read bytes in io->bufuse. If io->bufuse is 0, errno will probably
* be set. Returns io. */
* number of read bytes in io->bufuse and updating io->bytes. If io->bufuse is
* 0, errno will probably be set. Returns io. */
static struct Io *
Io_read(struct Io *io){
io->bufuse = read(io->fd, io->buf, io->bs);
io->bytes += (io->bufuse = read(io->fd, io->buf, io->bs));
return io;
}
/* Seeks io->seek bytes through *io's file descriptor, (counter-intuitively)
* returning -1 if successful and a sysexits.h exit code if an unrecoverable
* error occurred. */
static int
Io_seek(struct Io *io){
ssize_t (*op)(int, void *, size_t);
if(!fdisstd(io->fd) && lseek(io->fd, io->seek, SEEK_SET) != -1)
return -1;
else if(io->fl == write_flags){
/* cheat and use bufuse as the retval for write */
memset(io->buf, '\0', io->bs);
/* This is a dirty trick; rather than testing conditions and operating
* likewise, because the parameters to read or write are going to be
* the same either way, just use a function pointer to keep track of
* the intended operation. */
op = &write; /* Ignore -Wincompatible-pointer-types, it's fine. */
/* The difference is between const void * and void * which isn't
* significant enough to affect program behavior. */
}else
op = &read;
do{ if( (io->bufuse = (*op)(io->fd, io->buf, MIN(io->bs, io->seek))) == 0)
/* second chance */
io->bufuse = (*op)(io->fd, io->buf, MIN(io->bs, io->seek));
}while((io->seek -= io->bufuse) > 0 && io->bufuse != 0);
io->bufuse = 0;
return -1;
}
/* Sets the variables in a struct *io to the defaults. Identifies the read/
* write ends of the "pipe" by checking io->fl. Returns io. */
static struct Io *
Io_setdefaults(struct Io *io){
io->bs = 1024;
io->buf = NULL;
io->bytes = 0;
io->fd = (io->fl == read_flags) ? STDIN_FILENO : STDOUT_FILENO;
io->fn = (io->fl == read_flags) ? stdin_name : stdout_name;
io->prec = 0;
io->rec = 0;
io->seek = 0;
return io;
}
@ -130,52 +202,7 @@ Io_write(struct Io *io){
if((t = write(io->fd, io->buf, io->bufuse)) > 0)
memmove(io->buf, io->buf + t, (io->bufuse -= t));
return io;
}
/* Seeks io->seek bytes through *io's file descriptor, (counter-intuitively)
* returning -1 if successful and a sysexits.h exit code if an unrecoverable
* error occurred. */
static int
Io_seek(struct Io *io){
if(fdisnotstd(io->fd) && lseek(io->fd, io->seek, SEEK_SET) == -1)
return -1;
memset(io->buf, '\0', io->bs);
do{ if( (io->fl == read_flags
&& (((io->bufuse = read(io->fd, io->buf,
MIN(io->bs, io->seek))) != 0)
/* second chance if 0 */
|| ((io->bufuse = read(io->fd, io->buf,
MIN(io->bs, io->seek))) != 0)))
/* cheat and use bufuse as the retval for write
* (the buffer is zeroed, it doesn't matter) */
|| (io->fl == write_flags
&& ((io->bufuse = write(io->fd, io->buf,
MIN(io->bs, io->seek))) != 0)))
io->seek -= io->bufuse;
else
return EX_OK;
}while(io->seek > 0);
return -1;
}
/* Sets the variables in a struct *io to the defaults. Identifies the read/
* write ends of the "pipe" by checking io->fl. Returns io. */
static struct Io *
Io_setdefaults(struct Io *io){
io->bs = 1024;
io->buf = NULL;
io->fd = (io->fl == read_flags) ? STDIN_FILENO : STDOUT_FILENO;
io->fn = (io->fl == read_flags) ? stdin_name : stdout_name;
io->prec = 0;
io->rec = 0;
io->seek = 0;
io->bytes += t;
return io;
}
@ -183,15 +210,16 @@ Io_setdefaults(struct Io *io){
/* Parses the string s to an integer, returning either the integer or in the
* case of an error a negative integer. This is used for argument parsing
* (e.g. -B [int]) in dj and no negative integer would be valid anyway. */
static int
static long
parse(char *s){
int r;
long r;
errno = 0;
r = (int)strtol(s, &s, 0);
return (*s == '\0' /* empty string */ || errno != 0)
? -1
: r;
r = (long)strtol(s, &s, 0);
if(*s == '\0' /* no chars left unparsed */ && errno == 0)
return r;
else
return -1;
}
/* Prints an error message suitable for the event of an operating system error,
@ -209,20 +237,20 @@ oserr(char *argv0, char *s){
struct Io *
output(struct Io io[2]){
fprintf(stderr, "%d:%d > %d:%d\n", /* dd(1p) does %d+%d\n%d+%d\n */
io[0].rec, io[0].prec, io[1].rec, io[1].prec);;
fprintf(stderr, fmt_output,
io[0].rec, io[0].prec, io[1].rec, io[1].prec,
io[0].bytes, io[1].bytes);
return io;
}
static int
usage(char **argv){
usage(char *argv0){
fprintf(stderr, "Usage: %s (-fA) (-a [byte]) (-c [count]\n"
"\t(-i [input file]) (-b [input block size])"
" (-s [input offset])\n"
"\t(-o [output file]) (-B [output block size])"
" (-S [output offset])\n", ARGV0);
fprintf(stderr, "Usage: %s (-fAH) (-a [byte]) (-c [count])\n"
"\t(-i [input file]) (-b [input block size]) (-s [input offset])\n"
"\t(-o [output file]) (-B [output block size]) (-S [output offset])\n",
ARGV0(argv0));
return EX_USAGE;
}
@ -239,6 +267,7 @@ int main(int argc, char *argv[]){
/* defaults */
align = -1;
count = 0;
fmt_output = fmt_asv;
noerror = 0;
io[0].fl = read_flags;
Io_setdefaults(&io[0]);
@ -246,41 +275,46 @@ int main(int argc, char *argv[]){
Io_setdefaults(&io[1]);
if(argc > 0)
while((c = getopt(argc, argv, "aAc:i:b:fs:o:B:S:")) != -1)
if((c == 'i' || c == 'o')
&& Io_fdopen(&io[c == 'o'], optarg) != 0){ /* file args */
terminate(io);
return oserr(argv[0], optarg);
while((c = getopt(argc, argv, "a:Ac:i:b:fHs:o:B:S:")) != -1)
if(c == 'i' || c == 'o'){
if(Io_fdopen(&io[c == 'o'], optarg) == -1){
terminate(io);
return oserr(argv[0], optarg);
}
/* boolean/flag arguments */
}else if(c == 'f')
noerror = 1;
else if(c == 'A')
align = '\0';
else if(c == 'H')
fmt_output = fmt_human;
/* optarg */
else if(c == 'a' && optarg[0] != '\0' && optarg[1] == '\0')
align = optarg[0];
/* numeric args as a double negative to catch uncaught stuff */
else if(!((c == 'c' && (count = parse(optarg)) < 0)
|| (c == 'b' && (io[0].bs = parse(optarg)) < 0)
|| (c == 's' && (io[0].seek = parse(optarg)) < 0)
|| (c == 'B' && (io[1].bs = parse(optarg)) < 0)
|| (c == 'S' && (io[1].seek = parse(optarg)) < 0))){
/* numeric args */
else if(!((c == 'c' && (count = parse(optarg)) >= 0)
|| (c == 'b' && (io[0].bs = parse(optarg)) >= 0)
|| (c == 's' && (io[0].seek = parse(optarg)) >= 0)
|| (c == 'B' && (io[1].bs = parse(optarg)) >= 0)
|| (c == 'S' && (io[1].seek = parse(optarg)) >= 0))){
terminate(io);
return usage(argv);
return usage(argv[0]);
}
if(argc > optind)
return usage(argv);
if(argc > optind){
terminate(io);
return usage(argv[0]);
}
for(p = 0; p <= 1; ++p){
if(Io_bufalloc(&io[p]) == NULL){
fprintf(stderr, "%s: Failed to allocate %d bytes\n", ARGV0,
io[p].bs);
fprintf(stderr, "%s: Failed to allocate %d bytes\n",
ARGV0(argv[0]), io[p].bs);
terminate(io);
return EX_OSERR;
}else if(io[p].seek > 0) /* seek */
switch(Io_seek(&io[p])){
case EX_OK: terminate(output(io)); return EX_OK;
case EX_OK: output(io); terminate(io); return EX_OK;
}
}
@ -293,7 +327,7 @@ int main(int argc, char *argv[]){
else if(io[0].bufuse < io[0].bs){
++io[0].prec;
if(noerror){
output(io);
}else
count = 1;
if(align >= 0)
@ -301,26 +335,35 @@ int main(int argc, char *argv[]){
}else
++io[0].rec;
/* write */ while(io[0].bufuse > 0){
Io_bufxfer(&io[1], &io[0], MIN(io[0].bufuse, io[1].bs));
/* write */
do{ if(io[1].bs > io[0].bs){ /* io[1].bs > io[0].bs */
Io_bufxapp(&io[1], &io[0]);
if(io[0].bs + io[1].bufuse <= io[1].bs && count != 1)
continue; /* we could write more */
}else
Io_bufxfer(&io[1], &io[0], MIN(io[0].bufuse, io[1].bs));
c = io[1].bufuse;
Io_write(&io[1]);
if(!noerror && io[1].bufuse == c)
Io_write(&io[1]); /* second chance */
if(io[1].bufuse == c) /* no more love */
if(c == io[1].bufuse) /* no more love */
count = 1;
else if(c > io[1].bufuse && io[1].bufuse > 0){
io[1].prec += 1;
if(noerror){
output(io);
}else
count = 1;
}else if(io[1].bufuse == 0)
}else if(io[1].bufuse == 0 && c < io[1].bs)
++io[1].prec;
else
++io[1].rec;
}
}while(io[0].bufuse > 0);
}while(count == 0 || --count > 0);
terminate(output(io));
output(io);
terminate(io);
return EX_OK;
}