1 /*
2  * Copyright (c) 2024 Omar Polo <op@omarpolo.com>
3  *
4  * Permission to use, copy, modify, and distribute this software for any
5  * purpose with or without fee is hereby granted, provided that the above
6  * copyright notice and this permission notice appear in all copies.
7  *
8  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
9  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
10  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
11  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
12  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
13  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
14  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
15  */
16 
17 #include "compat.h"
18 
19 #include <sys/wait.h>
20 
21 #include <errno.h>
22 #include <fcntl.h>
23 #include <stdio.h>
24 #include <stdlib.h>
25 #include <stdint.h>
26 #include <string.h>
27 #include <unistd.h>
28 
29 #include "exec.h"
30 #include "minibuffer.h"
31 #include "ui.h"
32 
33 #define TMPFILE "/tmp/telescope.XXXXXXXXXX"
34 
35 int
36 exec_cmd(char **argv, enum exec_mode mode)
37 {
38 	char	**t;
39 	int 	 s, fd, ret;
40 	pid_t 	 pid;
41 
42 	if (argv == NULL)
43 		return (-1);
44 
45 	if (mode == EXEC_FOREGROUND) {
46 		ui_suspend();
47 
48 		fprintf(stderr, "%s: running", getprogname());
49 		for (t = argv; *t; ++t)
50 			fprintf(stderr, " %s", *t);
51 		fprintf(stderr, "\n");
52 		fflush(NULL);
53 	}
54 
55 	switch (pid = fork()) {
56 	case -1:
57 		message("failed to fork: %s", strerror(errno));
58 		return (-1);
59 	case 0:
60 		if (mode == EXEC_BACKGROUND) {
61 			if ((fd = open("/dev/null", O_RDWR)) == -1) {
62 				warn("can't open /dev/null");
63 				_exit(1);
64 			}
65 			(void)dup2(fd, 0);
66 			(void)dup2(fd, 1);
67 			(void)dup2(fd, 2);
68 			if (fd > 2)
69 				close(fd);
70 		}
71 		execvp(argv[0], argv);
72 		if (mode == EXEC_FOREGROUND) {
73 			warn("can't exec \"%s\"", argv[0]);
74 			fprintf(stderr, "Press enter to continue");
75 			fflush(stderr);
76 			read(0, &s, 1);
77 		}
78 		_exit(1);
79 	}
80 
81 	if (mode == EXEC_BACKGROUND)
82 		return (0);
83 
84 	do {
85 		ret = waitpid(pid, &s, 0);
86 	} while (ret == -1 && errno == EINTR);
87 
88 	ui_resume();
89 
90 	if (WIFSIGNALED(s) || WEXITSTATUS(s) != 0) {
91 		message("%s failed", *argv);
92 		return (-1);
93 	}
94 
95 	return (0);
96 }
97 
98 FILE *
99 exec_editor(void *data, size_t len)
100 {
101 	FILE		*fp;
102 	char		*editor;
103 	char		 sfn[sizeof(TMPFILE)];
104 	char		*argv[3];
105 	int		 fd;
106 
107 	strlcpy(sfn, TMPFILE, sizeof(sfn));
108 	if ((fd = mkstemp(sfn)) == -1) {
109 		message("failed to create a temp file: %s", strerror(errno));
110 		return (NULL);
111 	}
112 	(void) write(fd, data, len);
113 	close(fd);
114 
115 	if ((editor = getenv("VISUAL")) == NULL &&
116 	    (editor = getenv("EDITOR")) == NULL)
117 		editor = (char *)DEFAULT_EDITOR;
118 
119 	argv[0] = editor;
120 	argv[1] = sfn;
121 	argv[2] = NULL;
122 
123 	if (exec_cmd(argv, EXEC_FOREGROUND) == -1) {
124 		(void) unlink(sfn);
125 		return (NULL);
126 	}
127 
128 	if ((fp = fopen(sfn, "r")) == NULL) {
129 		message("can't open temp file!");
130 		(void) unlink(sfn);
131 		return (NULL);
132 	}
133 	(void) unlink(sfn);
134 
135 	return (fp);
136 }