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-rw-r--r--shell/Config.in20
-rw-r--r--shell/ash.c146
2 files changed, 108 insertions, 58 deletions
diff --git a/shell/Config.in b/shell/Config.in
index f9fb8488f..eb4616672 100644
--- a/shell/Config.in
+++ b/shell/Config.in
@@ -53,16 +53,22 @@ config CONFIG_ASH_JOB_CONTROL
help
Enable job control in the ash shell.
-config CONFIG_ASH_TIMEOUT
- bool " Enable read timeout support."
+config CONFIG_ASH_READ_NCHARS
+ bool " Enable 'read -n N' and 'read -s' support"
default n
- depends on CONFIG_ASH_JOB_CONTROL
+ depends on CONFIG_ASH
help
- This option provides read -t <seconds> support.
+ 'read -n N' will return a value after N characters have been read.
+ 'read -s' will read without echoing the user's input.
- read builtin which allows the function to pass control back
- if no character input is read from the terminal within a set
- number of seconds.
+config CONFIG_ASH_READ_TIMEOUT
+ bool " Enable 'read -t S' support."
+ default n
+ depends on CONFIG_ASH
+ help
+ 'read -t S' will return a value after S seconds have passed.
+ This implementation will allow fractional seconds, expressed
+ as a decimal fraction, e.g. 'read -t 2.5 foo'.
config CONFIG_ASH_ALIAS
bool " Enable alias support"
diff --git a/shell/ash.c b/shell/ash.c
index 5f6f7c6d3..7271535aa 100644
--- a/shell/ash.c
+++ b/shell/ash.c
@@ -105,7 +105,7 @@
#undef JOBS
#endif
-#if JOBS
+#if JOBS || defined(CONFIG_ASH_READ_NCHARS)
#include <termios.h>
#endif
@@ -12598,34 +12598,80 @@ readcmd(int argc, char **argv)
char *prompt;
const char *ifs;
char *p;
-#if defined(CONFIG_ASH_TIMEOUT)
- fd_set set;
- int timeout;
- struct timeval timeout_struct;
- struct termios tty, old_tty;
-#endif
int startword;
int status;
int i;
+#if defined(CONFIG_ASH_READ_NCHARS)
+ int nch_flag = 0;
+ int nchars = 0;
+ int silent = 0;
+ struct termios tty, old_tty;
+#endif
+#if defined(CONFIG_ASH_READ_TIMEOUT)
+ fd_set set;
+ struct timeval ts;
+
+ ts.tv_sec = ts.tv_usec = 0;
+#endif
rflag = 0;
prompt = NULL;
-#if defined(CONFIG_ASH_TIMEOUT)
- timeout = 0;
-
+#if defined(CONFIG_ASH_READ_NCHARS) && defined(CONFIG_ASH_READ_TIMEOUT)
+ while ((i = nextopt("p:rt:n:s")) != '\0')
+#elif defined(CONFIG_ASH_READ_NCHARS)
+ while ((i = nextopt("p:rn:s")) != '\0')
+#elif defined(CONFIG_ASH_READ_TIMEOUT)
while ((i = nextopt("p:rt:")) != '\0')
#else
while ((i = nextopt("p:r")) != '\0')
#endif
{
- if (i == 'p')
+ switch(i) {
+ case 'p':
prompt = optionarg;
- else if (i == 'r')
- rflag = 1;
-#if defined(CONFIG_ASH_TIMEOUT)
- else
- timeout = atoi(optionarg);
+ break;
+#if defined(CONFIG_ASH_READ_NCHARS)
+ case 'n':
+ nchars = strtol(optionarg, &p, 10);
+ if (*p)
+ error("invalid count");
+ nch_flag = (nchars > 0);
+ break;
+ case 's':
+ silent = 1;
+ break;
#endif
+#if defined(CONFIG_ASH_READ_TIMEOUT)
+ case 't':
+ ts.tv_sec = strtol(optionarg, &p, 10);
+ ts.tv_usec = 0;
+ if (*p == '.') {
+ char *p2;
+ if (*++p) {
+ int scale;
+ ts.tv_usec = strtol(p, &p2, 10);
+ if (*p2)
+ error("invalid timeout");
+ scale = p2 - p;
+ /* normalize to usec */
+ if (scale > 6)
+ error("invalid timeout");
+ while (scale++ < 6)
+ ts.tv_usec *= 10;
+ }
+ } else if (*p) {
+ error("invalid timeout");
+ }
+ if ( ! ts.tv_sec && ! ts.tv_usec)
+ error("invalid timeout");
+ break;
+#endif
+ case 'r':
+ rflag = 1;
+ break;
+ default:
+ break;
+ }
}
if (prompt && isatty(0)) {
out2str(prompt);
@@ -12634,49 +12680,42 @@ readcmd(int argc, char **argv)
error("arg count");
if ((ifs = bltinlookup("IFS")) == NULL)
ifs = defifs;
-#if defined(CONFIG_ASH_TIMEOUT)
- c = 0;
-#endif
- status = 0;
- startword = 1;
- backslash = 0;
-
- STARTSTACKSTR(p);
-#if defined(CONFIG_ASH_TIMEOUT)
- if (timeout > 0) {
+#if defined(CONFIG_ASH_READ_NCHARS)
+ if (nch_flag || silent) {
tcgetattr(0, &tty);
old_tty = tty;
+ if (nch_flag) {
+ tty.c_lflag &= ~ICANON;
+ tty.c_cc[VMIN] = nchars;
+ }
+ if (silent) {
+ tty.c_lflag &= ~(ECHO|ECHOK|ECHONL);
- /* cfmakeraw(...) disables too much; we just do this instead. */
- tty.c_lflag &= ~(ECHO|ECHONL|ICANON|IEXTEN);
+ }
tcsetattr(0, TCSANOW, &tty);
-
+ }
+#endif
+#if defined(CONFIG_ASH_READ_TIMEOUT)
+ if (ts.tv_sec || ts.tv_usec) {
FD_ZERO (&set);
FD_SET (0, &set);
- timeout_struct.tv_sec = timeout;
- timeout_struct.tv_usec = 0;
-
- if ((i = select (FD_SETSIZE, &set, NULL, NULL, &timeout_struct)) == 1)
- {
- read(0, &c, 1);
- if(c == '\n' || c == 4) /* Handle newlines and EOF */
- i = 0; /* Don't read further... */
- else
- STPUTC(c, p); /* Keep reading... */
+ i = select (FD_SETSIZE, &set, NULL, NULL, &ts);
+ if (!i) {
+#if defined(CONFIG_ASH_READ_NCHARS)
+ if (nch_flag)
+ tcsetattr(0, TCSANOW, &old_tty);
+#endif
+ return 1;
}
- tcsetattr(0, TCSANOW, &old_tty);
-
- /* Echo the character so the user knows it was read...
- Yes, this can be done by setting the ECHO flag, but that
- echoes ^D and other control characters at this state */
- if(c != 0)
- write(1, &c, 1);
-
- } else
- i = 1;
-
- for (;i == 1;)
+ }
+#endif
+ status = 0;
+ startword = 1;
+ backslash = 0;
+ STARTSTACKSTR(p);
+#if defined(CONFIG_ASH_READ_NCHARS)
+ while (!nch_flag || nchars--)
#else
for (;;)
#endif
@@ -12714,6 +12753,11 @@ put:
STPUTC(c, p);
}
}
+#if defined(CONFIG_ASH_READ_NCHARS)
+ if (nch_flag || silent)
+ tcsetattr(0, TCSANOW, &old_tty);
+#endif
+
STACKSTRNUL(p);
/* Remove trailing blanks */
while ((char *)stackblock() <= --p && strchr(ifs, *p) != NULL)