*/
#include "libbb.h"
#include "shell_common.h"
-#include <sys/resource.h> /* getrlimit */
const char defifsvar[] ALIGN1 = "IFS= \t\n";
+const char defoptindvar[] ALIGN1 = "OPTIND=1";
int FAST_FUNC is_well_formed_var_name(const char *s, char terminator)
/* read builtin */
-/* Needs to be interruptible: shell mush handle traps and shell-special signals
+/* Needs to be interruptible: shell must handle traps and shell-special signals
* while inside read. To implement this, be sure to not loop on EINTR
* and return errno == EINTR reliably.
*/
//Here we can simply store "VAR=" at buffer start and store read data directly
//after "=", then pass buffer to setvar() to consume.
const char* FAST_FUNC
-shell_builtin_read(void FAST_FUNC (*setvar)(const char *name, const char *val),
- char **argv,
- const char *ifs,
- int read_flags,
- const char *opt_n,
- const char *opt_p,
- const char *opt_t,
- const char *opt_u
-)
+shell_builtin_read(struct builtin_read_params *params)
{
+ struct pollfd pfd[1];
+#define fd (pfd[0].fd) /* -u FD */
unsigned err;
unsigned end_ms; /* -t TIMEOUT */
- int fd; /* -u FD */
int nchars; /* -n NUM */
char **pp;
char *buffer;
+ char delim;
struct termios tty, old_tty;
const char *retval;
int bufpos; /* need to be able to hold -1 */
int startword;
smallint backslash;
+ char **argv;
+ const char *ifs;
+ int read_flags;
errno = err = 0;
+ argv = params->argv;
pp = argv;
while (*pp) {
if (!is_well_formed_var_name(*pp, '\0')) {
}
nchars = 0; /* if != 0, -n is in effect */
- if (opt_n) {
- nchars = bb_strtou(opt_n, NULL, 10);
+ if (params->opt_n) {
+ nchars = bb_strtou(params->opt_n, NULL, 10);
if (nchars < 0 || errno)
return "invalid count";
/* note: "-n 0": off (bash 3.2 does this too) */
}
+
end_ms = 0;
- if (opt_t) {
- end_ms = bb_strtou(opt_t, NULL, 10);
- if (errno || end_ms > UINT_MAX / 2048)
+ if (params->opt_t && !ENABLE_FEATURE_SH_READ_FRAC) {
+ end_ms = bb_strtou(params->opt_t, NULL, 10);
+ if (errno)
return "invalid timeout";
+ if (end_ms > UINT_MAX / 2048) /* be safely away from overflow */
+ end_ms = UINT_MAX / 2048;
end_ms *= 1000;
-#if 0 /* even bash has no -t N.NNN support */
- ts.tv_sec = bb_strtou(opt_t, &p, 10);
- ts.tv_usec = 0;
- /* EINVAL means number is ok, but not terminated by NUL */
- if (*p == '.' && errno == EINVAL) {
- char *p2;
- if (*++p) {
- int scale;
- ts.tv_usec = bb_strtou(p, &p2, 10);
- if (errno)
- return "invalid timeout";
- scale = p2 - p;
- /* normalize to usec */
- if (scale > 6)
+ }
+ if (params->opt_t && ENABLE_FEATURE_SH_READ_FRAC) {
+ /* bash 4.3 (maybe earlier) supports -t N.NNNNNN */
+ char *p;
+ /* Eat up to three fractional digits */
+ int frac_digits = 3 + 1;
+
+ end_ms = bb_strtou(params->opt_t, &p, 10);
+ if (end_ms > UINT_MAX / 2048) /* be safely away from overflow */
+ end_ms = UINT_MAX / 2048;
+
+ if (errno) {
+ /* EINVAL = number is ok, but not NUL terminated */
+ if (errno != EINVAL || *p != '.')
+ return "invalid timeout";
+ /* Do not check the rest: bash allows "0.123456xyz" */
+ while (*++p && --frac_digits) {
+ end_ms *= 10;
+ end_ms += (*p - '0');
+ if ((unsigned char)(*p - '0') > 9)
return "invalid timeout";
- while (scale++ < 6)
- ts.tv_usec *= 10;
}
- } else if (ts.tv_sec < 0 || errno) {
- return "invalid timeout";
}
- if (!(ts.tv_sec | ts.tv_usec)) { /* both are 0? */
- return "invalid timeout";
+ while (--frac_digits > 0) {
+ end_ms *= 10;
}
-#endif /* if 0 */
}
+
fd = STDIN_FILENO;
- if (opt_u) {
- fd = bb_strtou(opt_u, NULL, 10);
+ if (params->opt_u) {
+ fd = bb_strtou(params->opt_u, NULL, 10);
if (fd < 0 || errno)
return "invalid file descriptor";
}
- if (opt_p && isatty(fd)) {
- fputs(opt_p, stderr);
+ if (params->opt_t && end_ms == 0) {
+ /* "If timeout is 0, read returns immediately, without trying
+ * to read any data. The exit status is 0 if input is available
+ * on the specified file descriptor, non-zero otherwise."
+ * bash seems to ignore -p PROMPT for this use case.
+ */
+ int r;
+ pfd[0].events = POLLIN;
+ r = poll(pfd, 1, /*timeout:*/ 0);
+ /* Return 0 only if poll returns 1 ("one fd ready"), else return 1: */
+ return (const char *)(uintptr_t)(r <= 0);
+ }
+
+ if (params->opt_p && isatty(fd)) {
+ fputs(params->opt_p, stderr);
fflush_all();
}
+ ifs = params->ifs;
if (ifs == NULL)
ifs = defifs;
+ read_flags = params->read_flags;
if (nchars || (read_flags & BUILTIN_READ_SILENT)) {
tcgetattr(fd, &tty);
old_tty = tty;
// Setting it to more than 1 breaks poll():
// it blocks even if there's data. !??
//tty.c_cc[VMIN] = nchars < 256 ? nchars : 255;
- /* reads would block only if < 1 char is available */
+ /* reads will block only if < 1 char is available */
tty.c_cc[VMIN] = 1;
/* no timeout (reads block forever) */
tty.c_cc[VTIME] = 0;
retval = (const char *)(uintptr_t)0;
startword = 1;
backslash = 0;
- if (end_ms) /* NB: end_ms stays nonzero: */
- end_ms = ((unsigned)monotonic_ms() + end_ms) | 1;
+ if (params->opt_t)
+ end_ms += (unsigned)monotonic_ms();
buffer = NULL;
bufpos = 0;
+ delim = params->opt_d ? params->opt_d[0] : '\n';
do {
char c;
- struct pollfd pfd[1];
int timeout;
if ((bufpos & 0xff) == 0)
buffer = xrealloc(buffer, bufpos + 0x101);
timeout = -1;
- if (end_ms) {
+ if (params->opt_t) {
timeout = end_ms - (unsigned)monotonic_ms();
+ /* ^^^^^^^^^^^^^ all values are unsigned,
+ * wrapping math is used here, good even if
+ * 32-bit unix time wrapped (year 2038+).
+ */
if (timeout <= 0) { /* already late? */
retval = (const char *)(uintptr_t)1;
goto ret;
* regardless of SA_RESTART-ness of that signal!
*/
errno = 0;
- pfd[0].fd = fd;
pfd[0].events = POLLIN;
- if (poll(pfd, 1, timeout) != 1) {
+ if (poll(pfd, 1, timeout) <= 0) {
/* timed out, or EINTR */
err = errno;
retval = (const char *)(uintptr_t)1;
c = buffer[bufpos];
if (c == '\0')
continue;
- if (backslash) {
- backslash = 0;
- if (c != '\n')
- goto put;
- continue;
- }
- if (!(read_flags & BUILTIN_READ_RAW) && c == '\\') {
- backslash = 1;
- continue;
+ if (!(read_flags & BUILTIN_READ_RAW)) {
+ if (backslash) {
+ backslash = 0;
+ if (c != '\n')
+ goto put;
+ continue;
+ }
+ if (c == '\\') {
+ backslash = 1;
+ continue;
+ }
}
- if (c == '\n')
+ if (c == delim) /* '\n' or -d CHAR */
break;
/* $IFS splitting. NOT done if we run "read"
* without variable names (bash compat).
* Thus, "read" and "read REPLY" are not the same.
*/
- if (argv[0]) {
+ if (!params->opt_d && argv[0]) {
/* http://www.opengroup.org/onlinepubs/9699919799/utilities/V3_chap02.html#tag_18_06_05 */
const char *is_ifs = strchr(ifs, c);
if (startword && is_ifs) {
if (argv[1] != NULL && is_ifs) {
buffer[bufpos] = '\0';
bufpos = 0;
- setvar(*argv, buffer);
+ params->setvar(*argv, buffer);
argv++;
/* can we skip one non-space ifs char? (2: yes) */
startword = isspace(c) ? 2 : 1;
if (argv[0]) {
/* Remove trailing space $IFS chars */
- while (--bufpos >= 0 && isspace(buffer[bufpos]) && strchr(ifs, buffer[bufpos]) != NULL)
+ while (--bufpos >= 0
+ && isspace(buffer[bufpos])
+ && strchr(ifs, buffer[bufpos]) != NULL
+ ) {
continue;
+ }
buffer[bufpos + 1] = '\0';
+
+ /* Last variable takes the entire remainder with delimiters
+ * (sans trailing whitespace $IFS),
+ * but ***only "if there are fewer vars than fields"(c)***!
+ * The "X:Y:" case below: there are two fields,
+ * and therefore last delimiter (:) is eaten:
+ * IFS=": "
+ * echo "X:Y:Z:" | (read x y; echo "|$x|$y|") # |X|Y:Z:|
+ * echo "X:Y:Z" | (read x y; echo "|$x|$y|") # |X|Y:Z|
+ * echo "X:Y:" | (read x y; echo "|$x|$y|") # |X|Y|, not |X|Y:|
+ * echo "X:Y : " | (read x y; echo "|$x|$y|") # |X|Y|
+ */
+ if (bufpos >= 0
+ && strchr(ifs, buffer[bufpos]) != NULL
+ ) {
+ /* There _is_ a non-whitespace IFS char */
+ /* Skip whitespace IFS char before it */
+ while (--bufpos >= 0
+ && isspace(buffer[bufpos])
+ && strchr(ifs, buffer[bufpos]) != NULL
+ ) {
+ continue;
+ }
+ /* Are there $IFS chars? */
+ if (strcspn(buffer, ifs) >= ++bufpos) {
+ /* No: last var takes one field, not more */
+ /* So, drop trailing IFS delims */
+ buffer[bufpos] = '\0';
+ }
+ }
+
/* Use the remainder as a value for the next variable */
- setvar(*argv, buffer);
+ params->setvar(*argv, buffer);
/* Set the rest to "" */
while (*++argv)
- setvar(*argv, "");
+ params->setvar(*argv, "");
} else {
/* Note: no $IFS removal */
buffer[bufpos] = '\0';
- setvar("REPLY", buffer);
+ params->setvar("REPLY", buffer);
}
ret:
errno = err;
return retval;
+#undef fd
}
/* ulimit builtin */
};
/* "-": treat args as parameters of option with ASCII code 1 */
-static const char ulimit_opt_string[] = "-HSa"
+static const char ulimit_opt_string[] ALIGN1 = "-HSa"
#ifdef RLIMIT_FSIZE
"f::"
#endif
val = limit->rlim_cur;
if (val == RLIM_INFINITY)
- printf("unlimited\n");
+ puts("unlimited");
else {
val >>= l->factor_shift;
printf("%llu\n", (long long) val);
* ulimit 123 -c2 -l 456
*/
- /* In case getopt was already called:
- * reset the libc getopt() function, which keeps internal state.
+ /* In case getopt() was already called:
+ * reset libc getopt() internal state.
*/
-#ifdef __GLIBC__
- optind = 0;
-#else /* BSD style */
- optind = 1;
- /* optreset = 1; */
-#endif
- /* optarg = NULL; opterr = 0; optopt = 0; - do we need this?? */
+ GETOPT_RESET();
- argc = 1;
- while (argv[argc])
- argc++;
+ argc = string_array_len(argv);
opts = 0;
while (1) {
/* bad option. getopt already complained. */
break;
}
-
} /* while (there are options) */
return 0;