remove unnecessary initializations
[git/git.git] / help.c
CommitLineData
70827b15
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1/*
2 * builtin-help.c
3 *
4 * Builtin help-related commands (help, usage, version)
5 */
83aa18ea 6#include <sys/ioctl.h>
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7#include "cache.h"
8#include "builtin.h"
9#include "exec_cmd.h"
10#include "common-cmds.h"
11
70827b15 12
82e5a82f 13/* most GUI terminals set COLUMNS (although some don't export it) */
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14static int term_columns(void)
15{
16 char *col_string = getenv("COLUMNS");
96f1e58f 17 int n_cols;
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18
19 if (col_string && (n_cols = atoi(col_string)) > 0)
20 return n_cols;
21
22#ifdef TIOCGWINSZ
23 {
24 struct winsize ws;
25 if (!ioctl(1, TIOCGWINSZ, &ws)) {
26 if (ws.ws_col)
27 return ws.ws_col;
28 }
29 }
30#endif
31
32 return 80;
33}
34
35static void oom(void)
36{
37 fprintf(stderr, "git: out of memory\n");
38 exit(1);
39}
40
41static inline void mput_char(char c, unsigned int num)
42{
43 while(num--)
44 putchar(c);
45}
46
47static struct cmdname {
48 size_t len;
49 char name[1];
50} **cmdname;
51static int cmdname_alloc, cmdname_cnt;
52
53static void add_cmdname(const char *name, int len)
54{
55 struct cmdname *ent;
56 if (cmdname_alloc <= cmdname_cnt) {
57 cmdname_alloc = cmdname_alloc + 200;
58 cmdname = realloc(cmdname, cmdname_alloc * sizeof(*cmdname));
59 if (!cmdname)
60 oom();
61 }
62 ent = malloc(sizeof(*ent) + len);
63 if (!ent)
64 oom();
65 ent->len = len;
66 memcpy(ent->name, name, len);
67 ent->name[len] = 0;
68 cmdname[cmdname_cnt++] = ent;
69}
70
71static int cmdname_compare(const void *a_, const void *b_)
72{
73 struct cmdname *a = *(struct cmdname **)a_;
74 struct cmdname *b = *(struct cmdname **)b_;
75 return strcmp(a->name, b->name);
76}
77
78static void pretty_print_string_list(struct cmdname **cmdname, int longest)
79{
80 int cols = 1, rows;
81 int space = longest + 1; /* min 1 SP between words */
82 int max_cols = term_columns() - 1; /* don't print *on* the edge */
83 int i, j;
84
85 if (space < max_cols)
86 cols = max_cols / space;
87 rows = (cmdname_cnt + cols - 1) / cols;
88
89 qsort(cmdname, cmdname_cnt, sizeof(*cmdname), cmdname_compare);
90
91 for (i = 0; i < rows; i++) {
92 printf(" ");
93
94 for (j = 0; j < cols; j++) {
95 int n = j * rows + i;
96 int size = space;
97 if (n >= cmdname_cnt)
98 break;
99 if (j == cols-1 || n + rows >= cmdname_cnt)
100 size = 1;
101 printf("%-*s", size, cmdname[n]->name);
102 }
103 putchar('\n');
104 }
105}
106
107static void list_commands(const char *exec_path, const char *pattern)
108{
109 unsigned int longest = 0;
110 char path[PATH_MAX];
111 int dirlen;
112 DIR *dir = opendir(exec_path);
113 struct dirent *de;
114
115 if (!dir) {
116 fprintf(stderr, "git: '%s': %s\n", exec_path, strerror(errno));
117 exit(1);
118 }
119
120 dirlen = strlen(exec_path);
121 if (PATH_MAX - 20 < dirlen) {
122 fprintf(stderr, "git: insanely long exec-path '%s'\n",
123 exec_path);
124 exit(1);
125 }
126
127 memcpy(path, exec_path, dirlen);
128 path[dirlen++] = '/';
129
130 while ((de = readdir(dir)) != NULL) {
131 struct stat st;
132 int entlen;
133
134 if (strncmp(de->d_name, "git-", 4))
135 continue;
136 strcpy(path+dirlen, de->d_name);
137 if (stat(path, &st) || /* stat, not lstat */
138 !S_ISREG(st.st_mode) ||
139 !(st.st_mode & S_IXUSR))
140 continue;
141
142 entlen = strlen(de->d_name);
5bb1cda5 143 if (has_extension(de->d_name, ".exe"))
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144 entlen -= 4;
145
146 if (longest < entlen)
147 longest = entlen;
148
149 add_cmdname(de->d_name + 4, entlen-4);
150 }
151 closedir(dir);
152
153 printf("git commands available in '%s'\n", exec_path);
154 printf("----------------------------");
155 mput_char('-', strlen(exec_path));
156 putchar('\n');
157 pretty_print_string_list(cmdname, longest - 4);
158 putchar('\n');
159}
160
161static void list_common_cmds_help(void)
162{
163 int i, longest = 0;
164
165 for (i = 0; i < ARRAY_SIZE(common_cmds); i++) {
166 if (longest < strlen(common_cmds[i].name))
167 longest = strlen(common_cmds[i].name);
168 }
169
170 puts("The most commonly used git commands are:");
171 for (i = 0; i < ARRAY_SIZE(common_cmds); i++) {
172 printf(" %s", common_cmds[i].name);
173 mput_char(' ', longest - strlen(common_cmds[i].name) + 4);
174 puts(common_cmds[i].help);
175 }
176 puts("(use 'git help -a' to get a list of all installed git commands)");
177}
178
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179static void show_man_page(const char *git_cmd)
180{
181 const char *page;
182
183 if (!strncmp(git_cmd, "git", 3))
184 page = git_cmd;
185 else {
186 int page_len = strlen(git_cmd) + 4;
187 char *p = malloc(page_len + 1);
188 strcpy(p, "git-");
189 strcpy(p + 4, git_cmd);
190 p[page_len] = 0;
191 page = p;
192 }
193
194 execlp("man", "man", page, NULL);
195}
196
822a7d50
RJ
197void help_unknown_cmd(const char *cmd)
198{
199 printf("git: '%s' is not a git-command\n\n", cmd);
200 list_common_cmds_help();
201 exit(1);
202}
203
a633fca0 204int cmd_version(int argc, const char **argv, const char *prefix)
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205{
206 printf("git version %s\n", git_version_string);
207 return 0;
208}
209
a633fca0 210int cmd_help(int argc, const char **argv, const char *prefix)
70827b15 211{
6acbcb92 212 const char *help_cmd = argc > 1 ? argv[1] : NULL;
822a7d50
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213 const char *exec_path = git_exec_path();
214
215 if (!help_cmd) {
216 printf("usage: %s\n\n", git_usage_string);
217 list_common_cmds_help();
218 exit(1);
219 }
220
221 else if (!strcmp(help_cmd, "--all") || !strcmp(help_cmd, "-a")) {
222 printf("usage: %s\n\n", git_usage_string);
223 if(exec_path)
224 list_commands(exec_path, "git-*");
225 exit(1);
226 }
227
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228 else
229 show_man_page(help_cmd);
822a7d50 230
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231 return 0;
232}
233
234