diff options
| -rw-r--r-- | grep.c | 61 |
1 files changed, 32 insertions, 29 deletions
@@ -531,16 +531,42 @@ static void show_line(struct grep_opt *opt, char *bol, char *eol, printf("%.*s\n", rest, bol); } +static void show_pre_context(struct grep_opt *opt, const char *name, char *buf, + char *bol, unsigned lno) +{ + unsigned cur = lno, from = 1; + + if (opt->pre_context < lno) + from = lno - opt->pre_context; + if (from <= opt->last_shown) + from = opt->last_shown + 1; + + /* Rewind. */ + while (bol > buf && cur > from) { + bol--; + while (bol > buf && bol[-1] != '\n') + bol--; + cur--; + } + + /* Back forward. */ + while (cur < lno) { + char *eol = bol; + + while (*eol != '\n') + eol++; + show_line(opt, bol, eol, name, cur, '-'); + bol = eol + 1; + cur++; + } +} + static int grep_buffer_1(struct grep_opt *opt, const char *name, char *buf, unsigned long size, int collect_hits) { char *bol = buf; unsigned long left = size; unsigned lno = 1; - struct pre_context_line { - char *bol; - char *eol; - } *prev = NULL, *pcl; unsigned last_hit = 0; int binary_match_only = 0; unsigned count = 0; @@ -561,9 +587,6 @@ static int grep_buffer_1(struct grep_opt *opt, const char *name, } } - if (opt->pre_context) - prev = xcalloc(opt->pre_context, sizeof(*prev)); - while (left) { char *eol, ch; int hit; @@ -610,21 +633,8 @@ static int grep_buffer_1(struct grep_opt *opt, const char *name, * the context which is nonsense, but the user * deserves to get that ;-). */ - if (opt->pre_context) { - unsigned from; - if (opt->pre_context < lno) - from = lno - opt->pre_context; - else - from = 1; - if (from <= opt->last_shown) - from = opt->last_shown + 1; - while (from < lno) { - pcl = &prev[lno-from-1]; - show_line(opt, pcl->bol, pcl->eol, - name, from, '-'); - from++; - } - } + if (opt->pre_context) + show_pre_context(opt, name, buf, bol, lno); if (!opt->count) show_line(opt, bol, eol, name, lno, ':'); last_hit = lno; @@ -636,12 +646,6 @@ static int grep_buffer_1(struct grep_opt *opt, const char *name, */ show_line(opt, bol, eol, name, lno, '-'); } - if (opt->pre_context) { - memmove(prev+1, prev, - (opt->pre_context-1) * sizeof(*prev)); - prev->bol = bol; - prev->eol = eol; - } next_line: bol = eol + 1; @@ -651,7 +655,6 @@ static int grep_buffer_1(struct grep_opt *opt, const char *name, lno++; } - free(prev); if (collect_hits) return 0; |