'--color-words' algorithm can be described as: 1. collect a the minus/plus lines of a diff hunk, divided into minus-lines and plus-lines; 2. break both minus-lines and plus-lines into words and place them into two mmfile_t with one word for each line; 3. use xdiff to run diff on the two mmfile_t to get the words level diff; And for the common parts of the both file, we output the plus side text. diff_words->current_plus is used to trace the current position of the plus file which printed. diff_words->last_minus is used to trace the last minus word printed. For '--graph' to work with '--color-words', we need to output the graph prefix on each line of color words output. Generally, there are two conditions on which we should output the prefix. 1. diff_words->last_minus == 0 && diff_words->current_plus == diff_words->plus.text.ptr that is: the plus text must start as a new line, and if there is no minus word printed, a graph prefix must be printed. 2. diff_words->current_plus > diff_words->plus.text.ptr && *(diff_words->current_plus - 1) == '\n' that is: a graph prefix must be printed following a '\n' Signed-off-by: Bo Yang <struggleyb.nku@xxxxxxxxx> --- diff.c | 106 +++++++++++++++++++++++++++++++++++++++++++++++++++++---------- 1 files changed, 89 insertions(+), 17 deletions(-) diff --git a/diff.c b/diff.c index 067260b..0e87dd2 100644 --- a/diff.c +++ b/diff.c @@ -624,7 +624,8 @@ struct diff_words_style diff_words_styles[] = { struct diff_words_data { struct diff_words_buffer minus, plus; const char *current_plus; - FILE *file; + int last_minus; + struct diff_options *opt; regex_t *word_regex; enum diff_words_type type; struct diff_words_style *style; @@ -633,10 +634,15 @@ struct diff_words_data { static int fn_out_diff_words_write_helper(FILE *fp, struct diff_words_style_elem *st_el, const char *newline, - size_t count, const char *buf) + size_t count, const char *buf, + const char *line_prefix) { + int print = 0; + while (count) { char *p = memchr(buf, '\n', count); + if (print) + fputs(line_prefix, fp); if (p != buf) { if (st_el->color && fputs(st_el->color, fp) < 0) return -1; @@ -654,6 +660,7 @@ static int fn_out_diff_words_write_helper(FILE *fp, return -1; count -= p + 1 - buf; buf = p + 1; + print = 1; } return 0; } @@ -664,11 +671,20 @@ static void fn_out_diff_words_aux(void *priv, char *line, unsigned long len) struct diff_words_style *style = diff_words->style; int minus_first, minus_len, plus_first, plus_len; const char *minus_begin, *minus_end, *plus_begin, *plus_end; + struct diff_options *opt = diff_words->opt; + struct strbuf *msgbuf; + char *line_prefix = ""; if (line[0] != '@' || parse_hunk_header(line, len, &minus_first, &minus_len, &plus_first, &plus_len)) return; + assert(opt); + if (opt->output_prefix) { + msgbuf = opt->output_prefix(opt, opt->output_prefix_data); + line_prefix = msgbuf->buf; + } + /* POSIX requires that first be decremented by one if len == 0... */ if (minus_len) { minus_begin = diff_words->minus.orig[minus_first].begin; @@ -684,21 +700,57 @@ static void fn_out_diff_words_aux(void *priv, char *line, unsigned long len) } else plus_begin = plus_end = diff_words->plus.orig[plus_first].end; - if (diff_words->current_plus != plus_begin) - fn_out_diff_words_write_helper(diff_words->file, + /* + * '--color-words' algorithm can be described as: + * + * 1. collect a the minus/plus lines of a diff hunk, divided into minus-lines and plus-lines; + * 2. break both minus-lines and plus-lines into words and place them into two + * mmfile_t with one word for each line; + * 3. use xdiff to run diff on the two mmfile_t to get the words level diff; + * + * And for the common parts of the both file, we output the plus side text. + * diff_words->current_plus is used to trace the current position of the plus file + * which printed. diff_words->last_minus is used to trace the last minus word + * printed. + * + * For '--graph' to work with '--color-words', we need to output the graph prefix + * on each line of color words output. Generally, there are two conditions on + * which we should output the prefix. + * 1. diff_words->last_minus == 0 && diff_words->current_plus == diff_words->plus.text.ptr + * that is: the plus text must start as a new line, and if there is no minus + * word printed, a graph prefix must be printed. + * 2. diff_words->current_plus > diff_words->plus.text.ptr && *(diff_words->current_plus - 1) == '\n' + * that is: a graph prefix must be printed following a '\n' + */ + if ((diff_words->last_minus == 0 && + diff_words->current_plus == diff_words->plus.text.ptr) || + (diff_words->current_plus > diff_words->plus.text.ptr && + *(diff_words->current_plus - 1) == '\n')) { + fputs(line_prefix, diff_words->opt->file); + } + if (diff_words->current_plus != plus_begin) { + fn_out_diff_words_write_helper(diff_words->opt->file, &style->ctx, style->newline, plus_begin - diff_words->current_plus, - diff_words->current_plus); - if (minus_begin != minus_end) - fn_out_diff_words_write_helper(diff_words->file, + diff_words->current_plus, line_prefix); + if (*(plus_begin - 1) == '\n') + fputs(line_prefix, diff_words->opt->file); + } + if (minus_begin != minus_end) { + fn_out_diff_words_write_helper(diff_words->opt->file, &style->old, style->newline, - minus_end - minus_begin, minus_begin); - if (plus_begin != plus_end) - fn_out_diff_words_write_helper(diff_words->file, + minus_end - minus_begin, minus_begin, + line_prefix); + } + if (plus_begin != plus_end) { + fn_out_diff_words_write_helper(diff_words->opt->file, &style->new, style->newline, - plus_end - plus_begin, plus_begin); + plus_end - plus_begin, plus_begin, + line_prefix); + } diff_words->current_plus = plus_end; + diff_words->last_minus = minus_first; } /* This function starts looking at *begin, and returns 0 iff a word was found. */ @@ -779,16 +831,29 @@ static void diff_words_show(struct diff_words_data *diff_words) mmfile_t minus, plus; struct diff_words_style *style = diff_words->style; + struct diff_options *opt = diff_words->opt; + struct strbuf *msgbuf; + char *line_prefix = ""; + + assert(opt); + if (opt->output_prefix) { + msgbuf = opt->output_prefix(opt, opt->output_prefix_data); + line_prefix = msgbuf->buf; + } + /* special case: only removal */ if (!diff_words->plus.text.size) { - fn_out_diff_words_write_helper(diff_words->file, + fputs(line_prefix, diff_words->opt->file); + fn_out_diff_words_write_helper(diff_words->opt->file, &style->old, style->newline, - diff_words->minus.text.size, diff_words->minus.text.ptr); + diff_words->minus.text.size, + diff_words->minus.text.ptr, line_prefix); diff_words->minus.text.size = 0; return; } diff_words->current_plus = diff_words->plus.text.ptr; + diff_words->last_minus = 0; memset(&xpp, 0, sizeof(xpp)); memset(&xecfg, 0, sizeof(xecfg)); @@ -802,11 +867,18 @@ static void diff_words_show(struct diff_words_data *diff_words) free(minus.ptr); free(plus.ptr); if (diff_words->current_plus != diff_words->plus.text.ptr + - diff_words->plus.text.size) - fn_out_diff_words_write_helper(diff_words->file, + diff_words->plus.text.size) { + if ((diff_words->current_plus == diff_words->plus.text.ptr && + diff_words->last_minus == 0) || + (diff_words->current_plus > diff_words->plus.text.ptr && + *(diff_words->current_plus - 1) == '\n')) + fputs(line_prefix, diff_words->opt->file); + fn_out_diff_words_write_helper(diff_words->opt->file, &style->ctx, style->newline, diff_words->plus.text.ptr + diff_words->plus.text.size - - diff_words->current_plus, diff_words->current_plus); + - diff_words->current_plus, diff_words->current_plus, + line_prefix); + } diff_words->minus.text.size = diff_words->plus.text.size = 0; } @@ -1905,8 +1977,8 @@ static void builtin_diff(const char *name_a, ecbdata.diff_words = xcalloc(1, sizeof(struct diff_words_data)); - ecbdata.diff_words->file = o->file; ecbdata.diff_words->type = o->word_diff; + ecbdata.diff_words->opt = o; if (!o->word_regex) o->word_regex = userdiff_word_regex(one); if (!o->word_regex) -- 1.6.0.4 -- To unsubscribe from this list: send the line "unsubscribe git" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html