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forked from bonsai/harakit

cat(1p): refactor to get no args working

This commit is contained in:
Emma Tebibyte 2023-08-13 23:30:03 -06:00
parent da2ebdb1e1
commit b57a7179a5
Signed by untrusted user: emma
GPG Key ID: 6D661C738815E7DD

133
src/cat.c
View File

@ -27,68 +27,7 @@
#include <string.h>
#include <unistd.h>
int main(int argc, char *argv[]) {
bool u = false;
int opt;
extern int optind;
while ((opt = getopt(argc, argv, "u")) != -1) {
switch (opt) {
/*
* From cat(1p):
*
* -u Write bytes from the input file to the standard output
* without delay as each is read.
*/
case 'u':
u = true;
break;
default:
printf("Usage: %s (-u) file...\n", argv[0]);
return EX_USAGE;
}
}
int i = 1;
FILE *file;
for (i = optind; i < argc; i++) {
/*
* From cat(1p):
*
* file A pathname of an input file. If no file operands are
* specified, the standard input shall be used. If a file is
* '-', the cat utility shall read from the standard input at
* that point in the sequence. The cat utility shall not close
* and reopen standard input when it is referenced in this way,
* but shall accept multiple occurrences of '-' as a file
* operand.
*/
if (argv[i] == "-" || argc == 1) {
file = stdin;
} else if ((file = fopen(argv[i], "r")) == NULL) {
switch (errno) {
case EACCES:
printf("%s: %s: Permission denied.\n", argv[0], argv[i]);
return EX_NOINPUT;
case EISDIR:
printf("%s: %s: Is a directory.\n", argv[0], argv[i]);
return EX_NOINPUT;
case ELOOP:
printf("%s: %s: Is a symbolic link loop.\n", argv[0], argv[i]);
return EX_UNAVAILABLE;
case EMFILE:
printf("%s: Internal error.\n", argv[0]);
return EX_SOFTWARE;
case ENOENT: case ENOTDIR: case ENXIO:
printf("%s: %s: No such file or directory.\n", argv[0], argv[i]);
return EX_NOINPUT;
default:
printf("%s: Unknown error.\n", argv[0]);
return EX_UNAVAILABLE;
}
}
void cat(FILE *file, bool u) {
int byte = 0; /* variable for storing bytes as they are read */
int p = 0; /* index counter for bytes in buffered reading */
char buf[4096]; /* buffer for buffered reading */
@ -113,6 +52,76 @@ int main(int argc, char *argv[]) {
fflush(stdout);
if (file != stdin) { fclose(file); }
}
int main(int argc, char *argv[]) {
bool u = false;
int opt;
int i;
extern int optind;
while ((opt = getopt(argc, argv, "u")) != -1) {
switch (opt) {
/*
* From cat(1p):
*
* -u Write bytes from the input file to the standard output
* without delay as each is read.
*/
case 'u':
u = true;
break;
default:
printf("Usage: %s (-u) file...\n", argv[0]);
return EX_USAGE;
}
}
/*
* From cat(1p):
*
* file A pathname of an input file. If no file operands are
* specified, the standard input shall be used. If a file is
* '-', the cat utility shall read from the standard input at
* that point in the sequence. The cat utility shall not close
* and reopen standard input when it is referenced in this way,
* but shall accept multiple occurrences of '-' as a file
* operand.
*/
if (optind == argc) {
cat(stdin, u);
}
FILE *file;
for (i = optind; i < argc; i++) {
if (argv[i][0] == '-' && argv[i][1] != '\0') {
continue;
} if (strcmp(argv[i], "-") == 0) {
file = stdin;
} else if ((file = fopen(argv[i], "r")) == NULL) {
switch (errno) {
case EACCES:
printf("%s: %s: Permission denied.\n", argv[0], argv[i]);
return EX_NOINPUT;
case EISDIR:
printf("%s: %s: Is a directory.\n", argv[0], argv[i]);
return EX_NOINPUT;
case ELOOP:
printf("%s: %s: Is a symbolic link loop.\n", argv[0], argv[i]);
return EX_UNAVAILABLE;
case EMFILE:
printf("%s: Internal error.\n", argv[0]);
return EX_SOFTWARE;
case ENOENT: case ENOTDIR: case ENXIO:
printf("%s: %s: No such file or directory.\n", argv[0], argv[i]);
return EX_NOINPUT;
default:
printf("%s: Unknown error.\n", argv[0]);
return EX_UNAVAILABLE;
}
}
cat(file, u);
}
return EX_OK;