1 files changed, 38 insertions, 31 deletions

diff --git a/miscutils/less.c b/miscutils/less.c
index d84df469c..554e54687 100644
--- a/miscutils/less.c
+++ b/miscutils/less.c
@@ -414,10 +414,10 @@ static void read_lines(void)
         char *current_line, *p;
         int w = width;
         char last_terminated = terminated;
+        time_t last_time = 0;
+        int retry_EAGAIN = 2;
 #if ENABLE_FEATURE_LESS_REGEXP
         unsigned old_max_fline = max_fline;
-        time_t last_time = 0;
-        int had_progress = 2;
 #endif
 
         /* (careful: max_fline can be -1) */
@@ -427,17 +427,14 @@ static void read_lines(void)
         if (option_mask32 & FLAG_N)
                 w -= 8;
 
- IF_FEATURE_LESS_REGEXP(again0:)
-
         p = current_line = ((char*)xmalloc(w + 4)) + 4;
-        max_fline += last_terminated;
         if (!last_terminated) {
                 const char *cp = flines[max_fline];
-                strcpy(p, cp);
-                p += strlen(current_line);
-                free(MEMPTR(flines[max_fline]));
+                p = stpcpy(p, cp);
+                free(MEMPTR(cp));
                 /* last_line_pos is still valid from previous read_lines() */
         } else {
+                max_fline++;
                 last_line_pos = 0;
         }
 
@@ -448,15 +445,29 @@ static void read_lines(void)
                         char c;
                         /* if no unprocessed chars left, eat more */
                         if (readpos >= readeof) {
-                                errno = 0;
-                                ndelay_on(0);
-                                eof_error = safe_read(STDIN_FILENO, readbuf, sizeof(readbuf));
-                                ndelay_off(0);
+                                int flags = ndelay_on(0);
+
+                                while (1) {
+                                        time_t t;
+
+                                        errno = 0;
+                                        eof_error = safe_read(STDIN_FILENO, readbuf, sizeof(readbuf));
+                                        if (errno != EAGAIN)
+                                                break;
+                                        t = time(NULL);
+                                        if (t != last_time) {
+                                                last_time = t;
+                                                if (--retry_EAGAIN < 0)
+                                                        break;
+                                        }
+                                        sched_yield();
+                                }
+                                fcntl(0, F_SETFL, flags); /* ndelay_off(0) */
                                 readpos = 0;
                                 readeof = eof_error;
                                 if (eof_error <= 0)
                                         goto reached_eof;
-                                IF_FEATURE_LESS_REGEXP(had_progress = 1;)
+                                retry_EAGAIN = 1;
                         }
                         c = readbuf[readpos];
                         /* backspace? [needed for manpages] */
@@ -491,6 +502,11 @@ static void read_lines(void)
                         *p++ = c;
                         *p = '\0';
                 } /* end of "read chars until we have a line" loop */
+#if 0
+//BUG: also triggers on this:
+// { printf "\nfoo\n"; sleep 1; printf "\nbar\n"; } | less
+// (resulting in lost empty line between "foo" and "bar" lines)
+// the "terminated" logic needs fixing (or explaining)
                 /* Corner case: linewrap with only "" wrapping to next line */
                 /* Looks ugly on screen, so we do not store this empty line */
                 if (!last_terminated && !current_line[0]) {
@@ -498,6 +514,7 @@ static void read_lines(void)
                         max_lineno++;
                         continue;
                 }
+#endif
  reached_eof:
                 last_terminated = terminated;
                 flines = xrealloc_vector(flines, 8, max_fline);
@@ -528,24 +545,7 @@ static void read_lines(void)
 #endif
                 }
                 if (eof_error <= 0) {
-#if !ENABLE_FEATURE_LESS_REGEXP
                         break;
-#else
-                        if (wanted_match < num_matches) {
-                                break;
-                        } /* else: goto_match() called us */
-                        if (errno == EAGAIN) {
-                                time_t t = time(NULL);
-                                if (t != last_time) {
-                                        last_time = t;
-                                        if (--had_progress < 0)
-                                                break;
-                                }
-                                sched_yield();
-                                goto again0;
-                        }
-                        break;
-#endif
                 }
                 max_fline++;
                 current_line = ((char*)xmalloc(w + 4)) + 4;
@@ -802,11 +802,18 @@ static void buffer_print(void)
         unsigned i;
 
         move_cursor(0, 0);
-        for (i = 0; i <= max_displayed_line; i++)
+        for (i = 0; i <= max_displayed_line; i++) {
                 if (pattern_valid)
                         print_found(buffer[i]);
                 else
                         print_ascii(buffer[i]);
+        }
+        if ((option_mask32 & FLAG_E)
+         && eof_error <= 0
+         && (max_fline - cur_fline) <= max_displayed_line
+        ) {
+                less_exit(EXIT_SUCCESS);
+        }
         status_print();
 }