Clarify git-cherry documentation.
[git] / log-tree.c
1 #include "cache.h"
2 #include "diff.h"
3 #include "commit.h"
4 #include "log-tree.h"
5
6 static void show_parents(struct commit *commit, int abbrev)
7 {
8         struct commit_list *p;
9         for (p = commit->parents; p ; p = p->next) {
10                 struct commit *parent = p->item;
11                 printf(" %s", diff_unique_abbrev(parent->object.sha1, abbrev));
12         }
13 }
14
15 void show_log(struct rev_info *opt, struct log_info *log, const char *sep)
16 {
17         static char this_header[16384];
18         struct commit *commit = log->commit, *parent = log->parent;
19         int abbrev = opt->diffopt.abbrev;
20         int abbrev_commit = opt->abbrev_commit ? opt->abbrev : 40;
21         const char *extra;
22         int len;
23
24         opt->loginfo = NULL;
25         if (!opt->verbose_header) {
26                 fputs(diff_unique_abbrev(commit->object.sha1, abbrev_commit), stdout);
27                 if (opt->parents)
28                         show_parents(commit, abbrev_commit);
29                 putchar('\n');
30                 return;
31         }
32
33         /*
34          * The "oneline" format has several special cases:
35          *  - The pretty-printed commit lacks a newline at the end
36          *    of the buffer, but we do want to make sure that we
37          *    have a newline there. If the separator isn't already
38          *    a newline, add an extra one.
39          *  - unlike other log messages, the one-line format does
40          *    not have an empty line between entries.
41          */
42         extra = "";
43         if (*sep != '\n' && opt->commit_format == CMIT_FMT_ONELINE)
44                 extra = "\n";
45         if (opt->shown_one && opt->commit_format != CMIT_FMT_ONELINE)
46                 putchar('\n');
47         opt->shown_one = 1;
48
49         /*
50          * Print header line of header..
51          */
52         printf("%s%s",
53                 opt->commit_format == CMIT_FMT_ONELINE ? "" : "commit ",
54                 diff_unique_abbrev(commit->object.sha1, abbrev_commit));
55         if (opt->parents)
56                 show_parents(commit, abbrev_commit);
57         if (parent)
58                 printf(" (from %s)", diff_unique_abbrev(parent->object.sha1, abbrev_commit));
59         putchar(opt->commit_format == CMIT_FMT_ONELINE ? ' ' : '\n');
60
61         /*
62          * And then the pretty-printed message itself
63          */
64         len = pretty_print_commit(opt->commit_format, commit, ~0u, this_header, sizeof(this_header), abbrev);
65         printf("%s%s%s", this_header, extra, sep);
66 }
67
68 int log_tree_diff_flush(struct rev_info *opt)
69 {
70         diffcore_std(&opt->diffopt);
71
72         if (diff_queue_is_empty()) {
73                 int saved_fmt = opt->diffopt.output_format;
74                 opt->diffopt.output_format = DIFF_FORMAT_NO_OUTPUT;
75                 diff_flush(&opt->diffopt);
76                 opt->diffopt.output_format = saved_fmt;
77                 return 0;
78         }
79
80         if (opt->loginfo && !opt->no_commit_id)
81                 show_log(opt, opt->loginfo, opt->diffopt.with_stat ? "---\n" : "\n");
82         diff_flush(&opt->diffopt);
83         return 1;
84 }
85
86 static int diff_root_tree(struct rev_info *opt,
87                           const unsigned char *new, const char *base)
88 {
89         int retval;
90         void *tree;
91         struct tree_desc empty, real;
92
93         tree = read_object_with_reference(new, tree_type, &real.size, NULL);
94         if (!tree)
95                 die("unable to read root tree (%s)", sha1_to_hex(new));
96         real.buf = tree;
97
98         empty.buf = "";
99         empty.size = 0;
100         retval = diff_tree(&empty, &real, base, &opt->diffopt);
101         free(tree);
102         log_tree_diff_flush(opt);
103         return retval;
104 }
105
106 static int do_diff_combined(struct rev_info *opt, struct commit *commit)
107 {
108         unsigned const char *sha1 = commit->object.sha1;
109
110         diff_tree_combined_merge(sha1, opt->dense_combined_merges, opt);
111         return !opt->loginfo;
112 }
113
114 /*
115  * Show the diff of a commit.
116  *
117  * Return true if we printed any log info messages
118  */
119 static int log_tree_diff(struct rev_info *opt, struct commit *commit, struct log_info *log)
120 {
121         int showed_log;
122         struct commit_list *parents;
123         unsigned const char *sha1 = commit->object.sha1;
124
125         if (!opt->diff)
126                 return 0;
127
128         /* Root commit? */
129         parents = commit->parents;
130         if (!parents) {
131                 if (opt->show_root_diff)
132                         diff_root_tree(opt, sha1, "");
133                 return !opt->loginfo;
134         }
135
136         /* More than one parent? */
137         if (parents && parents->next) {
138                 if (opt->ignore_merges)
139                         return 0;
140                 else if (opt->combine_merges)
141                         return do_diff_combined(opt, commit);
142
143                 /* If we show individual diffs, show the parent info */
144                 log->parent = parents->item;
145         }
146
147         showed_log = 0;
148         for (;;) {
149                 struct commit *parent = parents->item;
150
151                 diff_tree_sha1(parent->object.sha1, sha1, "", &opt->diffopt);
152                 log_tree_diff_flush(opt);
153
154                 showed_log |= !opt->loginfo;
155
156                 /* Set up the log info for the next parent, if any.. */
157                 parents = parents->next;
158                 if (!parents)
159                         break;
160                 log->parent = parents->item;
161                 opt->loginfo = log;
162         }
163         return showed_log;
164 }
165
166 int log_tree_commit(struct rev_info *opt, struct commit *commit)
167 {
168         struct log_info log;
169
170         log.commit = commit;
171         log.parent = NULL;
172         opt->loginfo = &log;
173
174         if (!log_tree_diff(opt, commit, &log) && opt->loginfo && opt->always_show_header) {
175                 log.parent = NULL;
176                 show_log(opt, opt->loginfo, "");
177         }
178         opt->loginfo = NULL;
179         return 0;
180 }