freshlybakedca.ke
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1#include "git-compat-util.h"
2#include "config.h"
3#include "editor.h"
4#include "pager.h"
5#include "run-command.h"
6#include "sigchain.h"
7#include "alias.h"
8
9int pager_use_color = 1;
10
11#ifndef DEFAULT_PAGER
12#define DEFAULT_PAGER "less"
13#endif
14
15static struct child_process pager_process;
16static char *pager_program;
17static int old_fd1 = -1, old_fd2 = -1;
18
19/* Is the value coming back from term_columns() just a guess? */
20static int term_columns_guessed;
21
22
23static void close_pager_fds(void)
24{
25 /* signal EOF to pager */
26 close(1);
27 if (old_fd2 != -1)
28 close(2);
29}
30
31static void finish_pager(void)
32{
33 fflush(stdout);
34 fflush(stderr);
35 close_pager_fds();
36 finish_command(&pager_process);
37}
38
39static void wait_for_pager_atexit(void)
40{
41 if (old_fd1 == -1)
42 return;
43
44 finish_pager();
45}
46
47void wait_for_pager(void)
48{
49 if (old_fd1 == -1)
50 return;
51
52 finish_pager();
53 sigchain_pop_common();
54 unsetenv("GIT_PAGER_IN_USE");
55 dup2(old_fd1, 1);
56 close(old_fd1);
57 old_fd1 = -1;
58 if (old_fd2 != -1) {
59 dup2(old_fd2, 2);
60 close(old_fd2);
61 old_fd2 = -1;
62 }
63}
64
65static void wait_for_pager_signal(int signo)
66{
67 if (old_fd1 == -1)
68 return;
69
70 close_pager_fds();
71 finish_command_in_signal(&pager_process);
72 sigchain_pop(signo);
73 raise(signo);
74}
75
76static int core_pager_config(const char *var, const char *value,
77 const struct config_context *ctx UNUSED,
78 void *data UNUSED)
79{
80 if (!strcmp(var, "core.pager"))
81 return git_config_string(&pager_program, var, value);
82 return 0;
83}
84
85const char *git_pager(struct repository *r, int stdout_is_tty)
86{
87 const char *pager;
88
89 if (!stdout_is_tty)
90 return NULL;
91
92 pager = getenv("GIT_PAGER");
93 if (!pager) {
94 if (!pager_program)
95 read_early_config(r,
96 core_pager_config, NULL);
97 pager = pager_program;
98 }
99 if (!pager)
100 pager = getenv("PAGER");
101 if (!pager)
102 pager = DEFAULT_PAGER;
103 if (!*pager || !strcmp(pager, "cat"))
104 pager = NULL;
105
106 return pager;
107}
108
109static void setup_pager_env(struct strvec *env)
110{
111 const char **argv;
112 int i;
113 char *pager_env = xstrdup(PAGER_ENV);
114 int n = split_cmdline(pager_env, &argv);
115
116 if (n < 0)
117 die("malformed build-time PAGER_ENV: %s",
118 split_cmdline_strerror(n));
119
120 for (i = 0; i < n; i++) {
121 char *cp = strchr(argv[i], '=');
122
123 if (!cp)
124 die("malformed build-time PAGER_ENV");
125
126 *cp = '\0';
127 if (!getenv(argv[i])) {
128 *cp = '=';
129 strvec_push(env, argv[i]);
130 }
131 }
132 free(pager_env);
133 free(argv);
134}
135
136void prepare_pager_args(struct child_process *pager_process, const char *pager)
137{
138 strvec_push(&pager_process->args, pager);
139 pager_process->use_shell = 1;
140 setup_pager_env(&pager_process->env);
141 pager_process->trace2_child_class = "pager";
142}
143
144void setup_pager(struct repository *r)
145{
146 static int once = 0;
147 const char *pager = git_pager(r, isatty(1));
148
149 if (!pager)
150 return;
151
152 /*
153 * After we redirect standard output, we won't be able to use an ioctl
154 * to get the terminal size. Let's grab it now, and then set $COLUMNS
155 * to communicate it to any sub-processes.
156 */
157 {
158 char buf[64];
159 xsnprintf(buf, sizeof(buf), "%d", term_columns());
160 if (!term_columns_guessed)
161 setenv("COLUMNS", buf, 0);
162 }
163
164 setenv("GIT_PAGER_IN_USE", "true", 1);
165
166 child_process_init(&pager_process);
167
168 /* spawn the pager */
169 prepare_pager_args(&pager_process, pager);
170 pager_process.in = -1;
171 strvec_push(&pager_process.env, "GIT_PAGER_IN_USE");
172 if (start_command(&pager_process))
173 die("unable to execute pager '%s'", pager);
174
175 /* original process continues, but writes to the pipe */
176 old_fd1 = dup(1);
177 dup2(pager_process.in, 1);
178 if (isatty(2)) {
179 old_fd2 = dup(2);
180 dup2(pager_process.in, 2);
181 }
182 close(pager_process.in);
183
184 sigchain_push_common(wait_for_pager_signal);
185
186 if (!once) {
187 once++;
188 atexit(wait_for_pager_atexit);
189 }
190}
191
192int pager_in_use(void)
193{
194 return git_env_bool("GIT_PAGER_IN_USE", 0);
195}
196
197/*
198 * Return cached value (if set) or $COLUMNS environment variable (if
199 * set and positive) or ioctl(1, TIOCGWINSZ).ws_col (if positive),
200 * and default to 80 if all else fails.
201 */
202int term_columns(void)
203{
204 static int term_columns_at_startup;
205
206 char *col_string;
207 int n_cols;
208
209 if (term_columns_at_startup)
210 return term_columns_at_startup;
211
212 term_columns_at_startup = 80;
213 term_columns_guessed = 1;
214
215 col_string = getenv("COLUMNS");
216 if (col_string && (n_cols = atoi(col_string)) > 0) {
217 term_columns_at_startup = n_cols;
218 term_columns_guessed = 0;
219 }
220#ifdef TIOCGWINSZ
221 else {
222 struct winsize ws;
223 if (!ioctl(1, TIOCGWINSZ, &ws) && ws.ws_col) {
224 term_columns_at_startup = ws.ws_col;
225 term_columns_guessed = 0;
226 }
227 }
228#endif
229
230 return term_columns_at_startup;
231}
232
233/*
234 * Clear the entire line, leave cursor in first column.
235 */
236void term_clear_line(void)
237{
238 if (!isatty(2))
239 return;
240 if (is_terminal_dumb())
241 /*
242 * Fall back to print a terminal width worth of space
243 * characters (hoping that the terminal is still as wide
244 * as it was upon the first call to term_columns()).
245 */
246 fprintf(stderr, "\r%*s\r", term_columns(), "");
247 else
248 /*
249 * On non-dumb terminals use an escape sequence to clear
250 * the whole line, no matter how wide the terminal.
251 */
252 fputs("\r\033[K", stderr);
253}
254
255/*
256 * How many columns do we need to show this number in decimal?
257 */
258int decimal_width(uintmax_t number)
259{
260 int width;
261
262 for (width = 1; number >= 10; width++)
263 number /= 10;
264 return width;
265}
266
267struct pager_command_config_data {
268 const char *cmd;
269 int want;
270 char *value;
271};
272
273static int pager_command_config(const char *var, const char *value,
274 const struct config_context *ctx UNUSED,
275 void *vdata)
276{
277 struct pager_command_config_data *data = vdata;
278 const char *cmd;
279
280 if (skip_prefix(var, "pager.", &cmd) && !strcmp(cmd, data->cmd)) {
281 int b = git_parse_maybe_bool(value);
282 if (b >= 0)
283 data->want = b;
284 else {
285 data->want = 1;
286 data->value = xstrdup(value);
287 }
288 }
289
290 return 0;
291}
292
293/* returns 0 for "no pager", 1 for "use pager", and -1 for "not specified" */
294int check_pager_config(struct repository *r, const char *cmd)
295{
296 struct pager_command_config_data data;
297
298 data.cmd = cmd;
299 data.want = -1;
300 data.value = NULL;
301
302 read_early_config(r, pager_command_config, &data);
303
304 if (data.value)
305 pager_program = data.value;
306 return data.want;
307}