diff --stat: allow custom diffstat output width.

This adds two parameters to "diff --stat".

 . --stat-width=72 tells that the page should fit on 72-column output.

 . --stat-name-width=30 tells that the filename part is limited
   to 30 columns.

Signed-off-by: Junio C Hamano <junkio@cox.net>

diff --git a/diff.c b/diff.c
index 443e24861ba1857822dbe8e3c831f8037e4e832e..8d299f4766eb97a19390e5ea3dde6f1c3e115a97 100644 (file)
--- a/diff.c
+++ b/diff.c
@@ -545,21 +545,64 @@ static void diffstat_consume(void *priv, char *line, unsigned long len)
                x->deleted++;
 }
 
-static const char pluses[] = "++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++";
-static const char minuses[]= "----------------------------------------------------------------------";
 const char mime_boundary_leader[] = "------------";
 
-static void show_stats(struct diffstat_t* data)
+static int scale_linear(int it, int width, int max_change)
+{
+       /*
+        * round(width * it / max_change);
+        */
+       return (it * width * 2 + max_change) / (max_change * 2);
+}
+
+static void show_name(const char *prefix, const char *name, int len)
+{
+       printf(" %s%-*s |", prefix, len, name);
+}
+
+static void show_graph(char ch, int cnt)
+{
+       if (cnt <= 0)
+               return;
+       while (cnt--)
+               putchar(ch);
+}
+
+static void show_stats(struct diffstat_t* data, struct diff_options *options)
 {
        int i, len, add, del, total, adds = 0, dels = 0;
-       int max, max_change = 0, max_len = 0;
+       int max_change = 0, max_len = 0;
        int total_files = data->nr;
+       int width, name_width;
 
        if (data->nr == 0)
                return;
 
+       width = options->stat_width ? options->stat_width : 80;
+       name_width = options->stat_name_width ? options->stat_name_width : 50;
+
+       /* Sanity: give at least 5 columns to the graph,
+        * but leave at least 10 columns for the name.
+        */
+       if (width < name_width + 15) {
+               if (name_width <= 25)
+                       width = name_width + 15;
+               else
+                       name_width = width - 15;
+       }
+
+       /* Find the longest filename and max number of changes */
        for (i = 0; i < data->nr; i++) {
                struct diffstat_file *file = data->files[i];
+               int change = file->added + file->deleted;
+
+               len = quote_c_style(file->name, NULL, NULL, 0);
+               if (len) {
+                       char *qname = xmalloc(len + 1);
+                       quote_c_style(file->name, qname, NULL, 0);
+                       free(file->name);
+                       file->name = qname;
+               }
 
                len = strlen(file->name);
                if (max_len < len)
@@ -567,54 +610,53 @@ static void show_stats(struct diffstat_t* data)
 
                if (file->is_binary || file->is_unmerged)
                        continue;
-               if (max_change < file->added + file->deleted)
-                       max_change = file->added + file->deleted;
+               if (max_change < change)
+                       max_change = change;
        }
 
+       /* Compute the width of the graph part;
+        * 10 is for one blank at the beginning of the line plus
+        * " | count " between the name and the graph.
+        *
+        * From here on, name_width is the width of the name area,
+        * and width is the width of the graph area.
+        */
+       name_width = (name_width < max_len) ? name_width : max_len;
+       if (width < (name_width + 10) + max_change)
+               width = width - (name_width + 10);
+       else
+               width = max_change;
+
        for (i = 0; i < data->nr; i++) {
                const char *prefix = "";
                char *name = data->files[i]->name;
                int added = data->files[i]->added;
                int deleted = data->files[i]->deleted;
-
-               if (0 < (len = quote_c_style(name, NULL, NULL, 0))) {
-                       char *qname = xmalloc(len + 1);
-                       quote_c_style(name, qname, NULL, 0);
-                       free(name);
-                       data->files[i]->name = name = qname;
-               }
+               int name_len;
 
                /*
                 * "scale" the filename
                 */
-               len = strlen(name);
-               max = max_len;
-               if (max > 50)
-                       max = 50;
-               if (len > max) {
+               len = name_width;
+               name_len = strlen(name);
+               if (name_width < name_len) {
                        char *slash;
                        prefix = "...";
-                       max -= 3;
-                       name += len - max;
+                       len -= 3;
+                       name += name_len - len;
                        slash = strchr(name, '/');
                        if (slash)
                                name = slash;
                }
-               len = max;
-
-               /*
-                * scale the add/delete
-                */
-               max = max_change;
-               if (max + len > 70)
-                       max = 70 - len;
 
                if (data->files[i]->is_binary) {
-                       printf(" %s%-*s |  Bin\n", prefix, len, name);
+                       show_name(prefix, name, len);
+                       printf("  Bin\n");
                        goto free_diffstat_file;
                }
                else if (data->files[i]->is_unmerged) {
-                       printf(" %s%-*s |  Unmerged\n", prefix, len, name);
+                       show_name(prefix, name, len);
+                       printf("  Unmerged\n");
                        goto free_diffstat_file;
                }
                else if (!data->files[i]->is_renamed &&
@@ -623,27 +665,32 @@ static void show_stats(struct diffstat_t* data)
                        goto free_diffstat_file;
                }
 
+               /*
+                * scale the add/delete
+                */
                add = added;
                del = deleted;
                total = add + del;
                adds += add;
                dels += del;
 
-               if (max_change > 0) {
-                       total = (total * max + max_change / 2) / max_change;
-                       add = (add * max + max_change / 2) / max_change;
+               if (width <= max_change) {
+                       total = scale_linear(total, width, max_change);
+                       add = scale_linear(add, width, max_change);
                        del = total - add;
                }
-               printf(" %s%-*s |%5d %.*s%.*s\n", prefix,
-                               len, name, added + deleted,
-                               add, pluses, del, minuses);
+               show_name(prefix, name, len);
+               printf("%5d ", added + deleted);
+               show_graph('+', add);
+               show_graph('-', del);
+               putchar('\n');
        free_diffstat_file:
                free(data->files[i]->name);
                free(data->files[i]);
        }
        free(data->files);
        printf(" %d files changed, %d insertions(+), %d deletions(-)\n",
-                       total_files, adds, dels);
+              total_files, adds, dels);
 }
 
 struct checkdiff_t {
@@ -1681,6 +1728,14 @@ int diff_opt_parse(struct diff_options *options, const char **av, int ac)
        }
        else if (!strcmp(arg, "--stat"))
                options->output_format |= DIFF_FORMAT_DIFFSTAT;
+       else if (!strncmp(arg, "--stat-width=", 13)) {
+               options->stat_width = strtoul(arg + 13, NULL, 10);
+               options->output_format |= DIFF_FORMAT_DIFFSTAT;
+       }
+       else if (!strncmp(arg, "--stat-name-width=", 18)) {
+               options->stat_name_width = strtoul(arg + 18, NULL, 10);
+               options->output_format |= DIFF_FORMAT_DIFFSTAT;
+       }
        else if (!strcmp(arg, "--check"))
                options->output_format |= DIFF_FORMAT_CHECKDIFF;
        else if (!strcmp(arg, "--summary"))
@@ -2438,7 +2493,7 @@ void diff_flush(struct diff_options *options)
                        if (check_pair_status(p))
                                diff_flush_stat(p, options, &diffstat);
                }
-               show_stats(&diffstat);
+               show_stats(&diffstat, options);
                separator++;
        }
 

diff --git a/diff.h b/diff.h
index b60a02e627415d4edaf5056e7f95b519b7fe8fc0..e06d0f41885fa6d224cb1904e6ee06dbc3324e12 100644 (file)
--- a/diff.h
+++ b/diff.h
@@ -69,6 +69,9 @@ struct diff_options {
        const char *stat_sep;
        long xdl_opts;
 
+       int stat_width;
+       int stat_name_width;
+
        int nr_paths;
        const char **paths;
        int *pathlens;