read_key: drop optimization where we read 3 bytes at once

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
This commit is contained in:
Denys Vlasenko 2009-05-29 10:39:06 +02:00
parent 171932d7ca
commit 4b7db4f2ca
4 changed files with 65 additions and 59 deletions

View File

@ -933,54 +933,6 @@ void bb_displayroutes(int noresolve, int netstatfmt) FAST_FUNC;
#endif
/* "Keycodes" that report an escape sequence.
* We use something which fits into signed char,
* yet doesn't represent any valid Unicode characher.
* Also, -1 is reserved for error indication and we don't use it. */
enum {
KEYCODE_UP = -2,
KEYCODE_DOWN = -3,
KEYCODE_RIGHT = -4,
KEYCODE_LEFT = -5,
KEYCODE_HOME = -6,
KEYCODE_END = -7,
KEYCODE_INSERT = -8,
KEYCODE_DELETE = -9,
KEYCODE_PAGEUP = -10,
KEYCODE_PAGEDOWN = -11,
#if 0
KEYCODE_FUN1 = -12,
KEYCODE_FUN2 = -13,
KEYCODE_FUN3 = -14,
KEYCODE_FUN4 = -15,
KEYCODE_FUN5 = -16,
KEYCODE_FUN6 = -17,
KEYCODE_FUN7 = -18,
KEYCODE_FUN8 = -19,
KEYCODE_FUN9 = -20,
KEYCODE_FUN10 = -21,
KEYCODE_FUN11 = -22,
KEYCODE_FUN12 = -23,
#endif
KEYCODE_CURSOR_POS = -0x100,
/* How long is the longest ESC sequence we know?
* We want it big enough to be able to contain
* cursor position sequence "ESC [ 9999 ; 9999 R"
*/
KEYCODE_BUFFER_SIZE = 16
};
/* Note: fd may be in blocking or non-blocking mode, both make sense.
* For one, less uses non-blocking mode.
* Only the first read syscall inside read_key may block indefinitely
* (unless fd is in non-blocking mode),
* subsequent reads will time out after a few milliseconds.
* Return of -1 means EOF or error (errno == 0 on EOF).
* buffer[0] is used as a counter of buffered chars and must be 0
* on first call.
*/
int64_t read_key(int fd, char *buffer) FAST_FUNC;
/* Networking */
int create_icmp_socket(void) FAST_FUNC;
int create_icmp6_socket(void) FAST_FUNC;
@ -1209,6 +1161,54 @@ unsigned long long bb_makedev(unsigned int major, unsigned int minor) FAST_FUNC;
#endif
/* "Keycodes" that report an escape sequence.
* We use something which fits into signed char,
* yet doesn't represent any valid Unicode characher.
* Also, -1 is reserved for error indication and we don't use it. */
enum {
KEYCODE_UP = -2,
KEYCODE_DOWN = -3,
KEYCODE_RIGHT = -4,
KEYCODE_LEFT = -5,
KEYCODE_HOME = -6,
KEYCODE_END = -7,
KEYCODE_INSERT = -8,
KEYCODE_DELETE = -9,
KEYCODE_PAGEUP = -10,
KEYCODE_PAGEDOWN = -11,
#if 0
KEYCODE_FUN1 = -12,
KEYCODE_FUN2 = -13,
KEYCODE_FUN3 = -14,
KEYCODE_FUN4 = -15,
KEYCODE_FUN5 = -16,
KEYCODE_FUN6 = -17,
KEYCODE_FUN7 = -18,
KEYCODE_FUN8 = -19,
KEYCODE_FUN9 = -20,
KEYCODE_FUN10 = -21,
KEYCODE_FUN11 = -22,
KEYCODE_FUN12 = -23,
#endif
KEYCODE_CURSOR_POS = -0x100,
/* How long is the longest ESC sequence we know?
* We want it big enough to be able to contain
* cursor position sequence "ESC [ 9999 ; 9999 R"
*/
KEYCODE_BUFFER_SIZE = 16
};
/* Note: fd may be in blocking or non-blocking mode, both make sense.
* For one, less uses non-blocking mode.
* Only the first read syscall inside read_key may block indefinitely
* (unless fd is in non-blocking mode),
* subsequent reads will time out after a few milliseconds.
* Return of -1 means EOF or error (errno == 0 on EOF).
* buffer[0] is used as a counter of buffered chars and must be 0
* on first call.
*/
int64_t read_key(int fd, char *buffer) FAST_FUNC;
#if ENABLE_FEATURE_EDITING
/* It's NOT just ENABLEd or disabled. It's a number: */
# ifdef CONFIG_FEATURE_EDITING_HISTORY

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@ -1451,10 +1451,13 @@ static int lineedit_read_key(char *read_key_buffer)
pfd.events = POLLIN;
do {
poll_again:
/* Wait for input. Can't just call read_key, it will return
* at once if stdin is in non-blocking mode. */
safe_poll(&pfd, 1, -1);
/* note: read_key sets errno to 0 on success: */
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, -1);
}
/* Note: read_key sets errno to 0 on success: */
ic = read_key(STDIN_FILENO, read_key_buffer);
if (ENABLE_FEATURE_EDITING_ASK_TERMINAL
&& (int32_t)ic == KEYCODE_CURSOR_POS

View File

@ -69,11 +69,14 @@ int64_t FAST_FUNC read_key(int fd, char *buffer)
errno = 0;
n = (unsigned char) *buffer++;
if (n == 0) {
/* If no data, block waiting for input. If we read more
* than the minimal ESC sequence size, the "n=0" below
* would instead have to figure out how much to keep,
* resulting in larger code. */
n = safe_read(fd, buffer, 3);
/* If no data, block waiting for input.
* 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
* "li" too, and cat was getting wrong input.
*/
n = safe_read(fd, buffer, 1);
if (n <= 0)
return -1;
}

View File

@ -1006,7 +1006,7 @@ static void restore_G_args(save_arg_t *sv, char **argv)
* Commands run in command substitution ("`cmd`")
* have SIGTTIN, SIGTTOU, SIGTSTP set to SIG_IGN.
*
* Ordinary commands have signals set to SIG_IGN/DFL set as inherited
* Ordinary commands have signals set to SIG_IGN/DFL as inherited
* by the shell from its parent.
*
* Siganls which differ from SIG_DFL action
@ -1285,7 +1285,7 @@ static int set_local_var(char *str, int flg_export, int flg_read_only)
if (strncmp(cur->varstr, str, name_len) != 0) {
if (!cur->next) {
/* Bail out. Note that now cur points
* to last var in linked list */
* to the last var in the linked list */
break;
}
cur = cur->next;