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lineedit: fix another corner case with bad unicode input

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function                                             old     new   delta
read_key                                             607     646     +39
readit                                                50      55      +5
getch_nowait                                         290     295      +5
hash_find                                            233     234      +1
xstrtoul_range_sfx                                   231     230      -1
passwd_main                                         1058    1056      -2
builtin_exit                                          45      43      -2
cmp_main                                             649     645      -4
lineedit_read_key                                    257     245     -12
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 4/5 up/down: 50/-21)             Total: 29 bytes

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
This commit is contained in:
Denys Vlasenko
2010-03-11 21:17:55 +01:00
parent b0a57abb79
commit 58f108eb33
6 changed files with 67 additions and 35 deletions
Download Patch File Download Diff File Expand all files Collapse all files

45
libbb/lineedit.c
View File

@@ -1658,27 +1658,28 @@ static void win_changed(int nsig)
static int lineedit_read_key(char *read_key_buffer)
{
int64_t ic;
struct pollfd pfd;
int delay = -1;
int timeout = -1;
#if ENABLE_FEATURE_ASSUME_UNICODE
char unicode_buf[MB_CUR_MAX + 1];
int unicode_idx = 0;
#endif
pfd.fd = STDIN_FILENO;
pfd.events = POLLIN;
do {
#if ENABLE_FEATURE_EDITING_ASK_TERMINAL || ENABLE_FEATURE_ASSUME_UNICODE
poll_again:
while (1) {
/* Wait for input. TIMEOUT = -1 makes read_key wait even
* on nonblocking stdin, TIMEOUT = 50 makes sure we won't
* insist on full MB_CUR_MAX buffer to declare input like
* "\xff\n",pause,"ls\n" invalid and thus won't lose "ls".
*
* Note: read_key sets errno to 0 on success.
*/
ic = read_key(STDIN_FILENO, read_key_buffer, timeout);
if (errno) {
#if ENABLE_FEATURE_ASSUME_UNICODE
if (errno == EAGAIN && unicode_idx != 0)
goto pushback;
#endif
if (read_key_buffer[0] == 0) {
/* Wait for input. Can't just call read_key,
* it returns at once if stdin
* is in non-blocking mode. */
safe_poll(&pfd, 1, delay);
break;
}
/* Note: read_key sets errno to 0 on success: */
ic = read_key(STDIN_FILENO, read_key_buffer);
#if ENABLE_FEATURE_EDITING_ASK_TERMINAL
if ((int32_t)ic == KEYCODE_CURSOR_POS
@@ -1695,7 +1696,7 @@ static int lineedit_read_key(char *read_key_buffer)
}
}
}
goto poll_again;
continue;
}
#endif
@@ -1704,19 +1705,20 @@ static int lineedit_read_key(char *read_key_buffer)
wchar_t wc;
if ((int32_t)ic < 0) /* KEYCODE_xxx */
return ic;
// TODO: imagine sequence like: 0xff, <left-arrow>: we are currently losing 0xff...
break;
// TODO: imagine sequence like: 0xff,<left-arrow>: we are currently losing 0xff...
unicode_buf[unicode_idx++] = ic;
unicode_buf[unicode_idx] = '\0';
if (mbstowcs(&wc, unicode_buf, 1) != 1) {
/* Not (yet?) a valid unicode char */
if (unicode_idx < MB_CUR_MAX) {
delay = 50;
goto poll_again;
timeout = 50;
continue;
}
pushback:
/* Invalid sequence. Save all "bad bytes" except first */
read_key_ungets(read_key_buffer, unicode_buf + 1, MB_CUR_MAX - 1);
read_key_ungets(read_key_buffer, unicode_buf + 1, unicode_idx - 1);
/*
* ic = unicode_buf[0] sounds even better, but currently
* this does not work: wchar_t[] -> char[] conversion
@@ -1730,7 +1732,8 @@ static int lineedit_read_key(char *read_key_buffer)
}
}
#endif
} while (errno == EAGAIN);
break;
}
return ic;
}

21
libbb/read_key.c
View File

@@ -9,7 +9,7 @@
*/
#include "libbb.h"
int64_t FAST_FUNC read_key(int fd, char *buffer)
int64_t FAST_FUNC read_key(int fd, char *buffer, int timeout)
{
struct pollfd pfd;
const char *seq;
@@ -90,14 +90,27 @@ int64_t FAST_FUNC read_key(int fd, char *buffer)
/* ESC [ Z - Shift-Tab */
};
pfd.fd = fd;
pfd.events = POLLIN;
buffer++; /* saved chars counter is in buffer[-1] now */
start_over:
errno = 0;
n = (unsigned char)buffer[-1];
if (n == 0) {
/* If no data, block waiting for input.
* It is tempting to read more than one byte here,
/* If no data, wait for input.
* If requested, wait TIMEOUT ms. TIMEOUT = -1 is useful
* if fd can be in non-blocking mode.
*/
if (timeout >= -1) {
if (safe_poll(&pfd, 1, timeout) == 0) {
/* Timed out */
errno = EAGAIN;
return -1;
}
}
/* It is tempting to read more than one byte here,
* but it breaks pasting. Example: at shell prompt,
* user presses "c","a","t" and then pastes "\nline\n".
* When we were reading 3 bytes here, we were eating
@@ -121,8 +134,6 @@ int64_t FAST_FUNC read_key(int fd, char *buffer)
}
/* Loop through known ESC sequences */
pfd.fd = fd;
pfd.events = POLLIN;
seq = esccmds;
while (*seq != '\0') {
/* n - position in sequence we did not read yet */