Merge branch 'jt/cache-tree-avoid-lazy-fetch-during-merge'
[git/git.git] / pager.c
CommitLineData
f67b45f8 1#include "cache.h"
b2141fc1 2#include "config.h"
ea27a18c 3#include "run-command.h"
a3da8821 4#include "sigchain.h"
65b5f948 5#include "alias.h"
f67b45f8 6
a3d023d0
JH
7#ifndef DEFAULT_PAGER
8#define DEFAULT_PAGER "less"
9#endif
10
d3180279 11static struct child_process pager_process = CHILD_PROCESS_INIT;
c0c08897 12static const char *pager_program;
ea27a18c 13
507d7804 14static void wait_for_pager(int in_signal)
bfdd9ffd 15{
507d7804
TI
16 if (!in_signal) {
17 fflush(stdout);
18 fflush(stderr);
19 }
bfdd9ffd
JS
20 /* signal EOF to pager */
21 close(1);
22 close(2);
507d7804
TI
23 if (in_signal)
24 finish_command_in_signal(&pager_process);
25 else
26 finish_command(&pager_process);
27}
28
29static void wait_for_pager_atexit(void)
30{
31 wait_for_pager(0);
bfdd9ffd 32}
f67b45f8 33
a3da8821
JK
34static void wait_for_pager_signal(int signo)
35{
507d7804 36 wait_for_pager(1);
a3da8821
JK
37 sigchain_pop(signo);
38 raise(signo);
39}
40
4babb839
JK
41static int core_pager_config(const char *var, const char *value, void *data)
42{
43 if (!strcmp(var, "core.pager"))
44 return git_config_string(&pager_program, var, value);
45 return 0;
46}
47
64778d24 48const char *git_pager(int stdout_is_tty)
f67b45f8 49{
63618245 50 const char *pager;
f67b45f8 51
64778d24 52 if (!stdout_is_tty)
63618245
JN
53 return NULL;
54
55 pager = getenv("GIT_PAGER");
cad3a205
JH
56 if (!pager) {
57 if (!pager_program)
eed27072 58 read_early_config(core_pager_config, NULL);
54adf370 59 pager = pager_program;
cad3a205 60 }
c27d205a
ML
61 if (!pager)
62 pager = getenv("PAGER");
402461aa 63 if (!pager)
a3d023d0 64 pager = DEFAULT_PAGER;
ed016612 65 if (!*pager || !strcmp(pager, "cat"))
63618245
JN
66 pager = NULL;
67
68 return pager;
69}
70
995bc22d
EW
71static void setup_pager_env(struct argv_array *env)
72{
73 const char **argv;
74 int i;
75 char *pager_env = xstrdup(PAGER_ENV);
76 int n = split_cmdline(pager_env, &argv);
77
78 if (n < 0)
79 die("malformed build-time PAGER_ENV: %s",
80 split_cmdline_strerror(n));
81
82 for (i = 0; i < n; i++) {
83 char *cp = strchr(argv[i], '=');
84
85 if (!cp)
86 die("malformed build-time PAGER_ENV");
87
88 *cp = '\0';
89 if (!getenv(argv[i])) {
90 *cp = '=';
91 argv_array_push(env, argv[i]);
92 }
93 }
94 free(pager_env);
95 free(argv);
96}
97
3e3a4a41
JH
98void prepare_pager_args(struct child_process *pager_process, const char *pager)
99{
100 argv_array_push(&pager_process->args, pager);
101 pager_process->use_shell = 1;
995bc22d 102 setup_pager_env(&pager_process->env_array);
eee73d1d 103 pager_process->trace2_child_class = "pager";
3e3a4a41
JH
104}
105
63618245
JN
106void setup_pager(void)
107{
64778d24 108 const char *pager = git_pager(isatty(1));
63618245 109
c0459ca4 110 if (!pager)
402461aa
JS
111 return;
112
ad6c3739 113 /*
be11f7ad
JK
114 * After we redirect standard output, we won't be able to use an ioctl
115 * to get the terminal size. Let's grab it now, and then set $COLUMNS
116 * to communicate it to any sub-processes.
ad6c3739 117 */
be11f7ad
JK
118 {
119 char buf[64];
120 xsnprintf(buf, sizeof(buf), "%d", term_columns());
121 setenv("COLUMNS", buf, 0);
122 }
ad6c3739 123
2e6c012e 124 setenv("GIT_PAGER_IN_USE", "true", 1);
85fb65ed 125
bfdd9ffd 126 /* spawn the pager */
3e3a4a41 127 prepare_pager_args(&pager_process, pager);
ea27a18c 128 pager_process.in = -1;
124b5190 129 argv_array_push(&pager_process.env_array, "GIT_PAGER_IN_USE");
bfdd9ffd
JS
130 if (start_command(&pager_process))
131 return;
132
133 /* original process continues, but writes to the pipe */
134 dup2(pager_process.in, 1);
a8335024
JH
135 if (isatty(2))
136 dup2(pager_process.in, 2);
bfdd9ffd
JS
137 close(pager_process.in);
138
139 /* this makes sure that the parent terminates after the pager */
a3da8821 140 sigchain_push_common(wait_for_pager_signal);
507d7804 141 atexit(wait_for_pager_atexit);
f67b45f8 142}
6e9af863
JK
143
144int pager_in_use(void)
145{
df2a6e38 146 return git_env_bool("GIT_PAGER_IN_USE", 0);
6e9af863 147}
ad6c3739
ZJS
148
149/*
150 * Return cached value (if set) or $COLUMNS environment variable (if
151 * set and positive) or ioctl(1, TIOCGWINSZ).ws_col (if positive),
152 * and default to 80 if all else fails.
153 */
154int term_columns(void)
155{
156 static int term_columns_at_startup;
157
158 char *col_string;
159 int n_cols;
160
161 if (term_columns_at_startup)
162 return term_columns_at_startup;
163
164 term_columns_at_startup = 80;
165
166 col_string = getenv("COLUMNS");
167 if (col_string && (n_cols = atoi(col_string)) > 0)
168 term_columns_at_startup = n_cols;
169#ifdef TIOCGWINSZ
170 else {
171 struct winsize ws;
172 if (!ioctl(1, TIOCGWINSZ, &ws) && ws.ws_col)
173 term_columns_at_startup = ws.ws_col;
174 }
175#endif
176
177 return term_columns_at_startup;
178}
4d9e079e 179
cd1096b2
SG
180/*
181 * Clear the entire line, leave cursor in first column.
182 */
183void term_clear_line(void)
184{
185 if (is_terminal_dumb())
186 /*
187 * Fall back to print a terminal width worth of space
188 * characters (hoping that the terminal is still as wide
189 * as it was upon the first call to term_columns()).
190 */
191 fprintf(stderr, "\r%*s\r", term_columns(), "");
192 else
193 /*
194 * On non-dumb terminals use an escape sequence to clear
195 * the whole line, no matter how wide the terminal.
196 */
197 fputs("\r\033[K", stderr);
198}
199
ec7ff5ba
ZJS
200/*
201 * How many columns do we need to show this number in decimal?
202 */
d306f3d3 203int decimal_width(uintmax_t number)
ec7ff5ba 204{
d306f3d3 205 int width;
ec7ff5ba 206
d306f3d3
JK
207 for (width = 1; number >= 10; width++)
208 number /= 10;
ec7ff5ba
ZJS
209 return width;
210}
4914c962 211
6a1e1bc0
JK
212struct pager_command_config_data {
213 const char *cmd;
214 int want;
215 char *value;
216};
217
218static int pager_command_config(const char *var, const char *value, void *vdata)
4914c962 219{
6a1e1bc0
JK
220 struct pager_command_config_data *data = vdata;
221 const char *cmd;
222
223 if (skip_prefix(var, "pager.", &cmd) && !strcmp(cmd, data->cmd)) {
89576613 224 int b = git_parse_maybe_bool(value);
4914c962 225 if (b >= 0)
6a1e1bc0 226 data->want = b;
4914c962 227 else {
6a1e1bc0
JK
228 data->want = 1;
229 data->value = xstrdup(value);
4914c962
NTND
230 }
231 }
6a1e1bc0
JK
232
233 return 0;
234}
235
236/* returns 0 for "no pager", 1 for "use pager", and -1 for "not specified" */
237int check_pager_config(const char *cmd)
238{
239 struct pager_command_config_data data;
240
241 data.cmd = cmd;
242 data.want = -1;
243 data.value = NULL;
244
eed27072 245 read_early_config(pager_command_config, &data);
6a1e1bc0
JK
246
247 if (data.value)
248 pager_program = data.value;
249 return data.want;
4914c962 250}