git-multimail: update to release 1.2.0
[git.git] / pager.c
blobe425070528f4f9fbf0953c9056d1ea43686e176f
1 #include "cache.h"
2 #include "run-command.h"
3 #include "sigchain.h"
5 #ifndef DEFAULT_PAGER
6 #define DEFAULT_PAGER "less"
7 #endif
9 /*
10 * This is split up from the rest of git so that we can do
11 * something different on Windows.
14 static const char *pager_argv[] = { NULL, NULL };
15 static struct child_process pager_process = CHILD_PROCESS_INIT;
17 static void wait_for_pager(int in_signal)
19 if (!in_signal) {
20 fflush(stdout);
21 fflush(stderr);
23 /* signal EOF to pager */
24 close(1);
25 close(2);
26 if (in_signal)
27 finish_command_in_signal(&pager_process);
28 else
29 finish_command(&pager_process);
32 static void wait_for_pager_atexit(void)
34 wait_for_pager(0);
37 static void wait_for_pager_signal(int signo)
39 wait_for_pager(1);
40 sigchain_pop(signo);
41 raise(signo);
44 const char *git_pager(int stdout_is_tty)
46 const char *pager;
48 if (!stdout_is_tty)
49 return NULL;
51 pager = getenv("GIT_PAGER");
52 if (!pager) {
53 if (!pager_program)
54 git_config(git_default_config, NULL);
55 pager = pager_program;
57 if (!pager)
58 pager = getenv("PAGER");
59 if (!pager)
60 pager = DEFAULT_PAGER;
61 if (!*pager || !strcmp(pager, "cat"))
62 pager = NULL;
64 return pager;
67 void setup_pager(void)
69 const char *pager = git_pager(isatty(1));
71 if (!pager)
72 return;
75 * force computing the width of the terminal before we redirect
76 * the standard output to the pager.
78 (void) term_columns();
80 setenv("GIT_PAGER_IN_USE", "true", 1);
82 /* spawn the pager */
83 pager_argv[0] = pager;
84 pager_process.use_shell = 1;
85 pager_process.argv = pager_argv;
86 pager_process.in = -1;
87 if (!getenv("LESS"))
88 argv_array_push(&pager_process.env_array, "LESS=FRX");
89 if (!getenv("LV"))
90 argv_array_push(&pager_process.env_array, "LV=-c");
91 argv_array_push(&pager_process.env_array, "GIT_PAGER_IN_USE");
92 if (start_command(&pager_process))
93 return;
95 /* original process continues, but writes to the pipe */
96 dup2(pager_process.in, 1);
97 if (isatty(2))
98 dup2(pager_process.in, 2);
99 close(pager_process.in);
101 /* this makes sure that the parent terminates after the pager */
102 sigchain_push_common(wait_for_pager_signal);
103 atexit(wait_for_pager_atexit);
106 int pager_in_use(void)
108 const char *env;
109 env = getenv("GIT_PAGER_IN_USE");
110 return env ? git_config_bool("GIT_PAGER_IN_USE", env) : 0;
114 * Return cached value (if set) or $COLUMNS environment variable (if
115 * set and positive) or ioctl(1, TIOCGWINSZ).ws_col (if positive),
116 * and default to 80 if all else fails.
118 int term_columns(void)
120 static int term_columns_at_startup;
122 char *col_string;
123 int n_cols;
125 if (term_columns_at_startup)
126 return term_columns_at_startup;
128 term_columns_at_startup = 80;
130 col_string = getenv("COLUMNS");
131 if (col_string && (n_cols = atoi(col_string)) > 0)
132 term_columns_at_startup = n_cols;
133 #ifdef TIOCGWINSZ
134 else {
135 struct winsize ws;
136 if (!ioctl(1, TIOCGWINSZ, &ws) && ws.ws_col)
137 term_columns_at_startup = ws.ws_col;
139 #endif
141 return term_columns_at_startup;
145 * How many columns do we need to show this number in decimal?
147 int decimal_width(uintmax_t number)
149 int width;
151 for (width = 1; number >= 10; width++)
152 number /= 10;
153 return width;
156 /* returns 0 for "no pager", 1 for "use pager", and -1 for "not specified" */
157 int check_pager_config(const char *cmd)
159 int want = -1;
160 struct strbuf key = STRBUF_INIT;
161 const char *value = NULL;
162 strbuf_addf(&key, "pager.%s", cmd);
163 if (git_config_key_is_valid(key.buf) &&
164 !git_config_get_value(key.buf, &value)) {
165 int b = git_config_maybe_bool(key.buf, value);
166 if (b >= 0)
167 want = b;
168 else {
169 want = 1;
170 pager_program = xstrdup(value);
173 strbuf_release(&key);
174 return want;