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authorDenys Vlasenko2010-01-12 22:11:24 +0100
committerDenys Vlasenko2010-01-12 22:11:24 +0100
commit7306727d1b2ed05afc91548ba374f7400a2389e3 (patch)
tree39cf4dff144f82dc9eaad30eae9c4fe67d405e4e /shell/builtin_read.c
parent6c93b24ce9dfb5c3970178ca2545502a7830716c (diff)
downloadbusybox-7306727d1b2ed05afc91548ba374f7400a2389e3.zip
busybox-7306727d1b2ed05afc91548ba374f7400a2389e3.tar.gz
shell: split read builtin from ash
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Diffstat (limited to 'shell/builtin_read.c')
-rw-r--r--shell/builtin_read.c205
1 files changed, 205 insertions, 0 deletions
diff --git a/shell/builtin_read.c b/shell/builtin_read.c
new file mode 100644
index 0000000..7f667e9
--- /dev/null
+++ b/shell/builtin_read.c
@@ -0,0 +1,205 @@
+/* vi: set sw=4 ts=4: */
+/*
+ * Adapted from ash applet code
+ *
+ * This code is derived from software contributed to Berkeley by
+ * Kenneth Almquist.
+ *
+ * Copyright (c) 1989, 1991, 1993, 1994
+ * The Regents of the University of California. All rights reserved.
+ *
+ * Copyright (c) 1997-2005 Herbert Xu <herbert@gondor.apana.org.au>
+ * was re-ported from NetBSD and debianized.
+ *
+ * Copyright (c) 2010 Denys Vlasenko
+ * Split from ash.c
+ *
+ * Licensed under the GPL v2 or later, see the file LICENSE in this tarball.
+ */
+#include "libbb.h"
+#include "shell_common.h"
+#include "builtin_read.h"
+
+const char* FAST_FUNC
+builtin_read(void (*setvar)(const char *name, const char *val, int flags),
+ char **argv,
+ const char *ifs,
+ int read_flags,
+ const char *opt_n,
+ const char *opt_p,
+ const char *opt_t,
+ const char *opt_u
+)
+{
+ static const char *const arg_REPLY[] = { "REPLY", NULL };
+
+ unsigned end_ms; /* -t TIMEOUT */
+ int fd; /* -u FD */
+ int nchars; /* -n NUM */
+ char *buffer;
+ struct termios tty, old_tty;
+ const char *retval;
+ int bufpos; /* need to be able to hold -1 */
+ int startword;
+ smallint backslash;
+
+ nchars = 0; /* if != 0, -n is in effect */
+ if (opt_n) {
+ nchars = bb_strtou(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)
+ return "invalid timeout";
+ 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)
+ 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";
+ }
+#endif /* if 0 */
+ }
+ fd = STDIN_FILENO;
+ if (opt_u) {
+ fd = bb_strtou(opt_u, NULL, 10);
+ if (fd < 0 || errno)
+ return "invalid file descriptor";
+ }
+
+ if (opt_p && isatty(fd)) {
+ fputs(opt_p, stderr);
+ fflush_all();
+ }
+
+ if (argv[0] == NULL)
+ argv = (char**)arg_REPLY;
+ if (ifs == NULL)
+ ifs = defifs;
+
+ if (nchars || (read_flags & BUILTIN_READ_SILENT)) {
+ tcgetattr(fd, &tty);
+ old_tty = tty;
+ if (nchars) {
+ tty.c_lflag &= ~ICANON;
+ tty.c_cc[VMIN] = nchars < 256 ? nchars : 255;
+ }
+ if (read_flags & BUILTIN_READ_SILENT) {
+ tty.c_lflag &= ~(ECHO | ECHOK | ECHONL);
+ }
+ /* This forces execution of "restoring" tcgetattr later */
+ read_flags |= BUILTIN_READ_SILENT;
+ /* if tcgetattr failed, tcsetattr will fail too.
+ * Ignoring, it's harmless. */
+ tcsetattr(fd, TCSANOW, &tty);
+ }
+
+ 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;
+ buffer = NULL;
+ bufpos = 0;
+ do {
+ char c;
+ const char *is_ifs;
+
+ if (end_ms) {
+ int timeout;
+ struct pollfd pfd[1];
+
+ pfd[0].fd = fd;
+ pfd[0].events = POLLIN;
+ timeout = end_ms - (unsigned)monotonic_ms();
+ if (timeout <= 0 /* already late? */
+ || safe_poll(pfd, 1, timeout) != 1 /* no? wait... */
+ ) { /* timed out! */
+ retval = (const char *)(uintptr_t)1;
+ goto ret;
+ }
+ }
+
+ if ((bufpos & 0xff) == 0)
+ buffer = xrealloc(buffer, bufpos + 0x100);
+ if (nonblock_safe_read(fd, &buffer[bufpos], 1) != 1) {
+ retval = (const char *)(uintptr_t)1;
+ break;
+ }
+ 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 (c == '\n')
+ break;
+ /* $IFS splitting */
+/* http://www.opengroup.org/onlinepubs/9699919799/utilities/V3_chap02.html#tag_18_06_05 */
+ is_ifs = strchr(ifs, c);
+ if (startword && is_ifs) {
+ if (isspace(c))
+ continue;
+ /* it is a non-space ifs char */
+ startword--;
+ if (startword == 1) /* first one? */
+ continue; /* yes, it is not next word yet */
+ }
+ startword = 0;
+ if (argv[1] != NULL && is_ifs) {
+ buffer[bufpos] = '\0';
+ bufpos = 0;
+ setvar(*argv, buffer, 0);
+ argv++;
+ /* can we skip one non-space ifs char? (2: yes) */
+ startword = isspace(c) ? 2 : 1;
+ continue;
+ }
+ put:
+ bufpos++;
+ } while (--nchars);
+
+ /* Remove trailing space ifs chars */
+ while (--bufpos >= 0 && isspace(buffer[bufpos]) && strchr(ifs, buffer[bufpos]) != NULL)
+ continue;
+ buffer[bufpos + 1] = '\0';
+
+ setvar(*argv, buffer, 0);
+
+ while (*++argv != NULL)
+ setvar(*argv, "", 0);
+ ret:
+ free(buffer);
+ if (read_flags & BUILTIN_READ_SILENT)
+ tcsetattr(fd, TCSANOW, &old_tty);
+ return retval;
+}