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authorDenis Vlasenko2006-12-25 01:23:02 +0000
committerDenis Vlasenko2006-12-25 01:23:02 +0000
commit5a4f0994b0ddd8ba8d96675382c42040ef516753 (patch)
tree23fb8e56edac5f408e95bad153af86ee5bd71331 /miscutils/less.c
parent7a50a64986758e0890e76411d5997c4a07d9c698 (diff)
downloadbusybox-5a4f0994b0ddd8ba8d96675382c42040ef516753.zip
busybox-5a4f0994b0ddd8ba8d96675382c42040ef516753.tar.gz
less: fix regexp search '/' on large files
Diffstat (limited to 'miscutils/less.c')
-rw-r--r--miscutils/less.c118
1 files changed, 71 insertions, 47 deletions
diff --git a/miscutils/less.c b/miscutils/less.c
index 290635d..60c54e6 100644
--- a/miscutils/less.c
+++ b/miscutils/less.c
@@ -11,14 +11,14 @@
* TODO:
* - Add more regular expression support - search modifiers, certain matches, etc.
* - Add more complex bracket searching - currently, nested brackets are
- * not considered.
+ * not considered.
* - Add support for "F" as an input. This causes less to act in
- * a similar way to tail -f.
+ * a similar way to tail -f.
* - Allow horizontal scrolling.
*
* Notes:
* - the inp file pointer is used so that keyboard input works after
- * redirected input has been read from stdin
+ * redirected input has been read from stdin
*/
#include "busybox.h"
@@ -130,7 +130,6 @@ static void less_exit(int code)
* and restore it when we exit. Less does this with the
* "ti" and "te" termcap commands; can this be done with
* only termios.h? */
-
putchar('\n');
fflush_stdout_and_exit(code);
}
@@ -158,12 +157,18 @@ static void print_statusline(const char *str)
printf(HIGHLIGHT"%.*s"NORMAL, width - 1, str);
}
+#if ENABLE_FEATURE_LESS_REGEXP
+static void fill_match_lines(unsigned pos);
+#else
+#define fill_match_lines(pos) ((void)0)
+#endif
+
+
static void read_lines(void)
{
- /* TODO: regexp match array should be updated too */
-
#define readbuf bb_common_bufsiz1
char *current_line, *p;
+ unsigned old_max_fline = max_fline;
int w = width;
char last_terminated = terminated;
@@ -179,6 +184,8 @@ static void read_lines(void)
cp += 8;
strcpy(current_line, cp);
p += strlen(current_line);
+ } else {
+ linepos = 0;
}
while (1) {
@@ -188,9 +195,9 @@ static void read_lines(void)
while (1) {
char c;
if (readpos >= readeof) {
-ndelay_on(0);
+ ndelay_on(0);
eof_error = safe_read(0, readbuf, sizeof(readbuf));
-ndelay_off(0);
+ ndelay_off(0);
readpos = 0;
readeof = eof_error;
if (eof_error < 0) {
@@ -254,16 +261,16 @@ ndelay_off(0);
p = current_line;
linepos = 0;
}
+ fill_match_lines(old_max_fline);
#undef readbuf
}
#if ENABLE_FEATURE_LESS_FLAGS
-
/* Interestingly, writing calc_percent as a function saves around 32 bytes
* on my build. */
static int calc_percent(void)
{
- unsigned p = 100 * (cur_fline + max_displayed_line) / (max_fline + 1);
+ unsigned p = (100 * (cur_fline+max_displayed_line+1) + max_fline/2) / (max_fline+1);
return p <= 100 ? p : 100;
}
@@ -288,7 +295,6 @@ static void m_status_print(void)
percentage = calc_percent();
printf("%i%%"NORMAL, percentage);
}
-
#endif
/* Print the status line */
@@ -479,9 +485,12 @@ static void buffer_up(int nlines)
static void buffer_line(int linenum)
{
+ if (linenum < 0)
+ linenum = 0;
+ cur_fline = linenum;
+ read_lines();
if (linenum + max_displayed_line > max_fline)
linenum = max_fline - max_displayed_line + TILDES;
- if (linenum < 0) linenum = 0;
cur_fline = linenum;
buffer_fill_and_print();
}
@@ -523,15 +532,24 @@ static void reinitialize(void)
buffer_fill_and_print();
}
-static char* getch_nowait(void)
+static void getch_nowait(char* input, int sz)
{
- static char input[16];
- ssize_t sz;
+ ssize_t rd;
fd_set readfds;
again:
fflush(stdout);
+
+ /* NB: select returns whenever read will not block. Therefore:
+ * (a) with O_NONBLOCK'ed fds select will return immediately
+ * (b) if eof is reached, select will also return
+ * because read will immediately return 0 bytes.
+ * Even if select says that input is available, read CAN block
+ * (switch fd into O_NONBLOCK'ed mode to avoid it)
+ */
FD_ZERO(&readfds);
- if (max_fline <= cur_fline + max_displayed_line && eof_error > 0) {
+ if (max_fline <= cur_fline + max_displayed_line
+ && eof_error > 0 /* did NOT reach eof yet */
+ ) {
/* We are interested in stdin */
FD_SET(0, &readfds);
}
@@ -541,17 +559,16 @@ static char* getch_nowait(void)
input[0] = '\0';
ndelay_on(kbd_fd);
- sz = read(kbd_fd, input, sizeof(input));
+ rd = read(kbd_fd, input, sz);
ndelay_off(kbd_fd);
- if (sz < 0) {
+ if (rd < 0) {
/* No keyboard input, but we have input on stdin! */
if (errno != EAGAIN) /* Huh?? */
- return input;
+ return;
read_lines();
buffer_fill_and_print();
goto again;
}
- return input;
}
/* Grab a character from input without requiring the return key. If the
@@ -559,10 +576,10 @@ static char* getch_nowait(void)
* special return codes. Note that this function works best with raw input. */
static int less_getch(void)
{
- char *input;
+ char input[16];
unsigned i;
again:
- input = getch_nowait();
+ getch_nowait(input, sizeof(input));
/* Detect escape sequences (i.e. arrow keys) and handle
* them accordingly */
@@ -718,6 +735,24 @@ static void goto_match(int match)
buffer_line(match_lines[normalize_match_pos(match)]);
}
+static void fill_match_lines(unsigned pos)
+{
+ if (!pattern_valid)
+ return;
+ /* Run the regex on each line of the current file */
+ while (pos <= max_fline) {
+ /* If this line matches */
+ if (regexec(&pattern, flines[pos], 0, NULL, 0) == 0
+ /* and we didn't match it last time */
+ && !(num_matches && match_lines[num_matches-1] == pos)
+ ) {
+ match_lines = xrealloc(match_lines, (num_matches+1) * sizeof(int));
+ match_lines[num_matches++] = pos;
+ }
+ pos++;
+ }
+}
+
static void regex_process(void)
{
char *uncomp_regex, *err;
@@ -751,24 +786,21 @@ static void regex_process(void)
return;
}
pattern_valid = 1;
+ match_pos = 0;
- /* Run the regex on each line of the current file */
- for (match_pos = 0; match_pos <= max_fline; match_pos++) {
- if (regexec(&pattern, flines[match_pos], 0, NULL, 0) == 0) {
- match_lines = xrealloc(match_lines, (num_matches+1) * sizeof(int));
- match_lines[num_matches++] = match_pos;
- }
- }
+ fill_match_lines(0);
if (num_matches == 0 || max_fline <= max_displayed_line) {
buffer_print();
return;
}
- for (match_pos = 0; match_pos < num_matches; match_pos++) {
+ while (match_pos < num_matches) {
if (match_lines[match_pos] > cur_fline)
break;
+ match_pos++;
}
- if (option_mask32 & LESS_STATE_MATCH_BACKWARDS) match_pos--;
+ if (option_mask32 & LESS_STATE_MATCH_BACKWARDS)
+ match_pos--;
buffer_line(match_lines[normalize_match_pos(match_pos)]);
}
#endif
@@ -809,11 +841,9 @@ static void number_process(int first_digit)
switch (keypress) {
case KEY_DOWN: case 'z': case 'd': case 'e': case ' ': case '\015':
buffer_down(num);
- buffer_print();
break;
case KEY_UP: case 'b': case 'w': case 'y': case 'u':
buffer_up(num);
- buffer_print();
break;
case 'g': case '<': case 'G': case '>':
cur_fline = num + max_displayed_line;
@@ -898,12 +928,13 @@ static void show_flag_status(void)
}
clear_line();
- printf(HIGHLIGHT"%s%u"NORMAL, "The status of the flag is: ", flag_val != 0);
+ printf(HIGHLIGHT"The status of the flag is: %u"NORMAL, flag_val != 0);
}
#endif
static void save_input_to_file(void)
{
+ const char *msg = "";
char *current_line;
int i;
FILE *fp;
@@ -912,19 +943,18 @@ static void save_input_to_file(void)
current_line = less_gets(sizeof("Log file: ")-1);
if (strlen(current_line) > 0) {
fp = fopen(current_line, "w");
- free(current_line);
if (!fp) {
- print_statusline("Error opening log file");
- return;
+ msg = "Error opening log file";
+ goto ret;
}
- for (i = 0; i < max_fline; i++)
+ for (i = 0; i <= max_fline; i++)
fprintf(fp, "%s\n", flines[i]);
fclose(fp);
- buffer_print();
- return;
+ msg = "Done";
}
+ ret:
+ print_statusline(msg);
free(current_line);
- print_statusline("No log file");
}
#if ENABLE_FEATURE_LESS_MARKS
@@ -1033,27 +1063,21 @@ static void keypress_process(int keypress)
switch (keypress) {
case KEY_DOWN: case 'e': case 'j': case 0x0d:
buffer_down(1);
- buffer_print();
break;
case KEY_UP: case 'y': case 'k':
buffer_up(1);
- buffer_print();
break;
case PAGE_DOWN: case ' ': case 'z':
buffer_down(max_displayed_line + 1);
- buffer_print();
break;
case PAGE_UP: case 'w': case 'b':
buffer_up(max_displayed_line + 1);
- buffer_print();
break;
case 'd':
buffer_down((max_displayed_line + 1) / 2);
- buffer_print();
break;
case 'u':
buffer_up((max_displayed_line + 1) / 2);
- buffer_print();
break;
case KEY_HOME: case 'g': case 'p': case '<': case '%':
buffer_line(0);