ps: conditionally enable -T on non-DESKTOP build too
[oweals/busybox.git] / miscutils / less.c
index 4f00fadb5d8b9e1de004851788364b8529e641de..ce77ddd3a1e1ceecc3d22fef5d2fc4aef58bed6b 100644 (file)
@@ -65,7 +65,7 @@ struct globals {
        int kbd_fd;  /* fd to get input from */
        int less_gets_pos;
 /* last position in last line, taking into account tabs */
-       size_t linepos;
+       size_t last_line_pos;
        unsigned max_fline;
        unsigned max_lineno; /* this one tracks linewrap */
        unsigned max_displayed_line;
@@ -97,12 +97,13 @@ struct globals {
 #endif
        smallint terminated;
        struct termios term_orig, term_less;
+       char kbd_input[KEYCODE_BUFFER_SIZE];
 };
 #define G (*ptr_to_globals)
 #define cur_fline           (G.cur_fline         )
 #define kbd_fd              (G.kbd_fd            )
 #define less_gets_pos       (G.less_gets_pos     )
-#define linepos             (G.linepos           )
+#define last_line_pos       (G.last_line_pos     )
 #define max_fline           (G.max_fline         )
 #define max_lineno          (G.max_lineno        )
 #define max_displayed_line  (G.max_displayed_line)
@@ -133,6 +134,7 @@ struct globals {
 #define terminated          (G.terminated        )
 #define term_orig           (G.term_orig         )
 #define term_less           (G.term_less         )
+#define kbd_input           (G.kbd_input         )
 #define INIT_G() do { \
        SET_PTR_TO_GLOBALS(xzalloc(sizeof(G))); \
        less_gets_pos = -1; \
@@ -141,7 +143,7 @@ struct globals {
        current_file = 1; \
        eof_error = 1; \
        terminated = 1; \
-       USE_FEATURE_LESS_REGEXP(wanted_match = -1;) \
+       IF_FEATURE_LESS_REGEXP(wanted_match = -1;) \
 } while (0)
 
 /* flines[] are lines read from stdin, each in malloc'ed buffer.
@@ -197,7 +199,7 @@ static void less_exit(int code)
 static void re_wrap(void)
 {
        int w = width;
-       int rem;
+       int new_line_pos;
        int src_idx;
        int dst_idx;
        int new_cur_fline = 0;
@@ -216,14 +218,16 @@ static void re_wrap(void)
        s = old_flines[0];
        lineno = LINENO(s);
        d = linebuf;
-       rem = w;
+       new_line_pos = 0;
        while (1) {
                *d = *s;
                if (*d != '\0') {
+                       new_line_pos++;
+                       if (*d == '\t') /* tab */
+                               new_line_pos += 7;
                        s++;
                        d++;
-                       rem--;
-                       if (rem == 0) {
+                       if (new_line_pos >= w) {
                                int sz;
                                /* new line is full, create next one */
                                *d = '\0';
@@ -235,28 +239,26 @@ static void re_wrap(void)
                                new_flines = xrealloc_vector(new_flines, 8, dst_idx);
                                new_flines[dst_idx] = d;
                                dst_idx++;
-                               if (rem) {
-                                       /* did we come here thru "goto next_new"? */
+                               if (new_line_pos < w) {
+                                       /* if we came here thru "goto next_new" */
                                        if (src_idx > max_fline)
                                                break;
                                        lineno = LINENO(s);
                                }
                                d = linebuf;
-                               rem = w;
+                               new_line_pos = 0;
                        }
                        continue;
                }
                /* *d == NUL: old line ended, go to next old one */
                free(MEMPTR(old_flines[src_idx]));
                /* btw, convert cur_fline... */
-               if (cur_fline == src_idx) {
+               if (cur_fline == src_idx)
                        new_cur_fline = dst_idx;
-               }
                src_idx++;
                /* no more lines? finish last new line (and exit the loop) */
-               if (src_idx > max_fline) {
+               if (src_idx > max_fline)
                        goto next_new;
-               }
                s = old_flines[src_idx];
                if (lineno != LINENO(s)) {
                        /* this is not a continuation line!
@@ -269,10 +271,12 @@ static void re_wrap(void)
        flines = (const char **)new_flines;
 
        max_fline = dst_idx - 1;
-       linepos = 0; // XXX
+       last_line_pos = new_line_pos;
        cur_fline = new_cur_fline;
        /* max_lineno is screen-size independent */
+#if ENABLE_FEATURE_LESS_REGEXP
        pattern_valid = 0;
+#endif
 }
 #endif
 
@@ -301,7 +305,7 @@ static void fill_match_lines(unsigned pos);
  *      on line wrap, only on "real" new lines.
  * readbuf[0..readeof-1] - small preliminary buffer.
  * readbuf[readpos] - next character to add to current line.
- * linepos - screen line position of next char to be read
+ * last_line_pos - screen line position of next char to be read
  *      (takes into account tabs and backspaces)
  * eof_error - < 0 error, == 0 EOF, > 0 not EOF/error
  */
@@ -320,7 +324,7 @@ static void read_lines(void)
        if (option_mask32 & FLAG_N)
                w -= 8;
 
USE_FEATURE_LESS_REGEXP(again0:)
IF_FEATURE_LESS_REGEXP(again0:)
 
        p = current_line = ((char*)xmalloc(w + 4)) + 4;
        max_fline += last_terminated;
@@ -329,9 +333,9 @@ static void read_lines(void)
                strcpy(p, cp);
                p += strlen(current_line);
                free(MEMPTR(flines[max_fline]));
-               /* linepos is still valid from previous read_lines() */
+               /* last_line_pos is still valid from previous read_lines() */
        } else {
-               linepos = 0;
+               last_line_pos = 0;
        }
 
        while (1) { /* read lines until we reach cur_fline or wanted_match */
@@ -353,28 +357,28 @@ static void read_lines(void)
                        /* backspace? [needed for manpages] */
                        /* <tab><bs> is (a) insane and */
                        /* (b) harder to do correctly, so we refuse to do it */
-                       if (c == '\x8' && linepos && p[-1] != '\t') {
+                       if (c == '\x8' && last_line_pos && p[-1] != '\t') {
                                readpos++; /* eat it */
-                               linepos--;
+                               last_line_pos--;
                        /* was buggy (p could end up <= current_line)... */
                                *--p = '\0';
                                continue;
                        }
                        {
-                               size_t new_linepos = linepos + 1;
+                               size_t new_last_line_pos = last_line_pos + 1;
                                if (c == '\t') {
-                                       new_linepos += 7;
-                                       new_linepos &= (~7);
+                                       new_last_line_pos += 7;
+                                       new_last_line_pos &= (~7);
                                }
-                               if ((int)new_linepos >= w)
+                               if ((int)new_last_line_pos >= w)
                                        break;
-                               linepos = new_linepos;
+                               last_line_pos = new_last_line_pos;
                        }
                        /* ok, we will eat this char */
                        readpos++;
                        if (c == '\n') {
                                terminated = 1;
-                               linepos = 0;
+                               last_line_pos = 0;
                                break;
                        }
                        /* NUL is substituted by '\n'! */
@@ -449,7 +453,7 @@ static void read_lines(void)
                max_fline++;
                current_line = ((char*)xmalloc(w + 4)) + 4;
                p = current_line;
-               linepos = 0;
+               last_line_pos = 0;
        } /* end of "read lines until we reach cur_fline" loop */
        fill_match_lines(old_max_fline);
 #if ENABLE_FEATURE_LESS_REGEXP
@@ -620,7 +624,7 @@ static void print_found(const char *line)
 
        while (match_status == 0) {
                char *new = xasprintf("%s%.*s"HIGHLIGHT"%.*s"NORMAL,
-                               growline ? : "",
+                               growline ? growline : "",
                                match_structs.rm_so, str,
                                match_structs.rm_eo - match_structs.rm_so,
                                                str + match_structs.rm_so);
@@ -768,9 +772,7 @@ static void buffer_line(int linenum)
 static void open_file_and_read_lines(void)
 {
        if (filename) {
-               int fd = xopen(filename, O_RDONLY);
-               dup2(fd, 0);
-               if (fd) close(fd);
+               xmove_fd(xopen(filename, O_RDONLY), STDIN_FILENO);
        } else {
                /* "less" with no arguments in argv[] */
                /* For status line only */
@@ -778,7 +780,7 @@ static void open_file_and_read_lines(void)
        }
        readpos = 0;
        readeof = 0;
-       linepos = 0;
+       last_line_pos = 0;
        terminated = 1;
        read_lines();
 }
@@ -802,9 +804,8 @@ static void reinitialize(void)
        buffer_fill_and_print();
 }
 
-static ssize_t getch_nowait(void)
+static int getch_nowait(void)
 {
-       char input[KEYCODE_BUFFER_SIZE];
        int rd;
        struct pollfd pfd[2];
 
@@ -835,36 +836,43 @@ static ssize_t getch_nowait(void)
        if (less_gets_pos >= 0)
                move_cursor(max_displayed_line + 2, less_gets_pos + 1);
        fflush(stdout);
+
+       if (kbd_input[0] == 0) { /* if nothing is buffered */
 #if ENABLE_FEATURE_LESS_WINCH
-       while (1) {
-               int r;
-               /* NB: SIGWINCH interrupts poll() */
-               r = poll(pfd + rd, 2 - rd, -1);
-               if (/*r < 0 && errno == EINTR &&*/ winch_counter)
-                       return '\\'; /* anything which has no defined function */
-               if (r) break;
-       }
+               while (1) {
+                       int r;
+                       /* NB: SIGWINCH interrupts poll() */
+                       r = poll(pfd + rd, 2 - rd, -1);
+                       if (/*r < 0 && errno == EINTR &&*/ winch_counter)
+                               return '\\'; /* anything which has no defined function */
+                       if (r) break;
+               }
 #else
-       safe_poll(pfd + rd, 2 - rd, -1);
+               safe_poll(pfd + rd, 2 - rd, -1);
 #endif
+       }
 
        /* We have kbd_fd in O_NONBLOCK mode, read inside read_key()
         * would not block even if there is no input available */
-       rd = read_key(kbd_fd, NULL, input);
-       if (rd == -1 && errno == EAGAIN) {
-               /* No keyboard input available. Since poll() did return,
-                * we should have input on stdin */
-               read_lines();
-               buffer_fill_and_print();
-               goto again;
+       rd = read_key(kbd_fd, kbd_input);
+       if (rd == -1) {
+               if (errno == EAGAIN) {
+                       /* No keyboard input available. Since poll() did return,
+                        * we should have input on stdin */
+                       read_lines();
+                       buffer_fill_and_print();
+                       goto again;
+               }
+               /* EOF/error (ssh session got killed etc) */
+               less_exit(0);
        }
        set_tty_cooked();
        return rd;
 }
 
-/* Grab a character from input without requiring the return key. If the
- * character is ASCII \033, get more characters and assign certain sequences
- * special return codes. Note that this function works best with raw input. */
+/* Grab a character from input without requiring the return key.
+ * May return KEYCODE_xxx values.
+ * Note that this function works best with raw input. */
 static int less_getch(int pos)
 {
        int i;
@@ -1499,7 +1507,7 @@ int less_main(int argc, char **argv)
        /* TODO: -x: do not interpret backspace, -xx: tab also */
        /* -xxx: newline also */
        /* -w N: assume width N (-xxx -w 32: hex viewer of sorts) */
-       getopt32(argv, "EMmN~I" USE_FEATURE_LESS_DASHCMD("S"));
+       getopt32(argv, "EMmN~I" IF_FEATURE_LESS_DASHCMD("S"));
        argc -= optind;
        argv += optind;
        num_files = argc;