Commit | Line | Data |
---|---|---|
2f4ce5ec JP |
1 | #include <linux/compiler.h> |
2 | #include <linux/string.h> | |
3 | #include <sys/types.h> | |
4 | #include <sys/stat.h> | |
5 | #include <unistd.h> | |
f37a291c | 6 | #include <string.h> |
2f4ce5ec JP |
7 | #include <stdlib.h> |
8 | #include <stdio.h> | |
901421a5 | 9 | #include "subcmd-util.h" |
4b6ab94e | 10 | #include "exec-cmd.h" |
2f4ce5ec | 11 | #include "subcmd-config.h" |
f37a291c | 12 | |
07800601 | 13 | #define MAX_ARGS 32 |
2f4ce5ec | 14 | #define PATH_MAX 4096 |
07800601 | 15 | |
07800601 IM |
16 | static const char *argv_exec_path; |
17 | static const char *argv0_path; | |
18 | ||
096d3558 JP |
19 | void exec_cmd_init(const char *exec_name, const char *prefix, |
20 | const char *exec_path, const char *exec_path_env) | |
21 | { | |
22 | subcmd_config.exec_name = exec_name; | |
23 | subcmd_config.prefix = prefix; | |
24 | subcmd_config.exec_path = exec_path; | |
25 | subcmd_config.exec_path_env = exec_path_env; | |
26 | } | |
27 | ||
2f4ce5ec JP |
28 | #define is_dir_sep(c) ((c) == '/') |
29 | ||
30 | static int is_absolute_path(const char *path) | |
31 | { | |
32 | return path[0] == '/'; | |
33 | } | |
34 | ||
35 | static const char *get_pwd_cwd(void) | |
36 | { | |
37 | static char cwd[PATH_MAX + 1]; | |
38 | char *pwd; | |
39 | struct stat cwd_stat, pwd_stat; | |
40 | if (getcwd(cwd, PATH_MAX) == NULL) | |
41 | return NULL; | |
42 | pwd = getenv("PWD"); | |
43 | if (pwd && strcmp(pwd, cwd)) { | |
44 | stat(cwd, &cwd_stat); | |
45 | if (!stat(pwd, &pwd_stat) && | |
46 | pwd_stat.st_dev == cwd_stat.st_dev && | |
47 | pwd_stat.st_ino == cwd_stat.st_ino) { | |
48 | strlcpy(cwd, pwd, PATH_MAX); | |
49 | } | |
50 | } | |
51 | return cwd; | |
52 | } | |
53 | ||
54 | static const char *make_nonrelative_path(const char *path) | |
55 | { | |
56 | static char buf[PATH_MAX + 1]; | |
57 | ||
58 | if (is_absolute_path(path)) { | |
59 | if (strlcpy(buf, path, PATH_MAX) >= PATH_MAX) | |
60 | die("Too long path: %.*s", 60, path); | |
61 | } else { | |
62 | const char *cwd = get_pwd_cwd(); | |
63 | if (!cwd) | |
64 | die("Cannot determine the current working directory"); | |
65 | if (snprintf(buf, PATH_MAX, "%s/%s", cwd, path) >= PATH_MAX) | |
66 | die("Too long path: %.*s", 60, path); | |
67 | } | |
68 | return buf; | |
69 | } | |
70 | ||
c4068f51 | 71 | char *system_path(const char *path) |
07800601 | 72 | { |
901421a5 | 73 | char *buf = NULL; |
07800601 IM |
74 | |
75 | if (is_absolute_path(path)) | |
c4068f51 | 76 | return strdup(path); |
07800601 | 77 | |
901421a5 JP |
78 | astrcatf(&buf, "%s/%s", subcmd_config.prefix, path); |
79 | ||
80 | return buf; | |
07800601 IM |
81 | } |
82 | ||
46113a54 | 83 | const char *extract_argv0_path(const char *argv0) |
07800601 IM |
84 | { |
85 | const char *slash; | |
86 | ||
87 | if (!argv0 || !*argv0) | |
88 | return NULL; | |
89 | slash = argv0 + strlen(argv0); | |
90 | ||
91 | while (argv0 <= slash && !is_dir_sep(*slash)) | |
92 | slash--; | |
93 | ||
94 | if (slash >= argv0) { | |
151f85a4 ACM |
95 | argv0_path = strndup(argv0, slash - argv0); |
96 | return argv0_path ? slash + 1 : NULL; | |
07800601 IM |
97 | } |
98 | ||
99 | return argv0; | |
100 | } | |
101 | ||
46113a54 | 102 | void set_argv_exec_path(const char *exec_path) |
07800601 IM |
103 | { |
104 | argv_exec_path = exec_path; | |
105 | /* | |
106 | * Propagate this setting to external programs. | |
107 | */ | |
096d3558 | 108 | setenv(subcmd_config.exec_path_env, exec_path, 1); |
07800601 IM |
109 | } |
110 | ||
111 | ||
46113a54 JP |
112 | /* Returns the highest-priority location to look for subprograms. */ |
113 | char *get_argv_exec_path(void) | |
07800601 | 114 | { |
c4068f51 | 115 | char *env; |
07800601 IM |
116 | |
117 | if (argv_exec_path) | |
c4068f51 | 118 | return strdup(argv_exec_path); |
07800601 | 119 | |
096d3558 | 120 | env = getenv(subcmd_config.exec_path_env); |
c4068f51 MH |
121 | if (env && *env) |
122 | return strdup(env); | |
07800601 | 123 | |
096d3558 | 124 | return system_path(subcmd_config.exec_path); |
07800601 IM |
125 | } |
126 | ||
901421a5 | 127 | static void add_path(char **out, const char *path) |
07800601 IM |
128 | { |
129 | if (path && *path) { | |
130 | if (is_absolute_path(path)) | |
901421a5 | 131 | astrcat(out, path); |
07800601 | 132 | else |
901421a5 | 133 | astrcat(out, make_nonrelative_path(path)); |
07800601 | 134 | |
901421a5 | 135 | astrcat(out, ":"); |
07800601 IM |
136 | } |
137 | } | |
138 | ||
139 | void setup_path(void) | |
140 | { | |
141 | const char *old_path = getenv("PATH"); | |
901421a5 | 142 | char *new_path = NULL; |
46113a54 | 143 | char *tmp = get_argv_exec_path(); |
07800601 | 144 | |
c4068f51 | 145 | add_path(&new_path, tmp); |
07800601 | 146 | add_path(&new_path, argv0_path); |
c4068f51 | 147 | free(tmp); |
07800601 IM |
148 | |
149 | if (old_path) | |
901421a5 | 150 | astrcat(&new_path, old_path); |
07800601 | 151 | else |
901421a5 | 152 | astrcat(&new_path, "/usr/local/bin:/usr/bin:/bin"); |
07800601 | 153 | |
901421a5 | 154 | setenv("PATH", new_path, 1); |
07800601 | 155 | |
901421a5 | 156 | free(new_path); |
07800601 IM |
157 | } |
158 | ||
46113a54 | 159 | static const char **prepare_exec_cmd(const char **argv) |
07800601 IM |
160 | { |
161 | int argc; | |
162 | const char **nargv; | |
163 | ||
164 | for (argc = 0; argv[argc]; argc++) | |
165 | ; /* just counting */ | |
166 | nargv = malloc(sizeof(*nargv) * (argc + 2)); | |
167 | ||
096d3558 | 168 | nargv[0] = subcmd_config.exec_name; |
07800601 IM |
169 | for (argc = 0; argv[argc]; argc++) |
170 | nargv[argc + 1] = argv[argc]; | |
171 | nargv[argc + 1] = NULL; | |
172 | return nargv; | |
173 | } | |
174 | ||
46113a54 JP |
175 | int execv_cmd(const char **argv) { |
176 | const char **nargv = prepare_exec_cmd(argv); | |
07800601 IM |
177 | |
178 | /* execvp() can only ever return if it fails */ | |
096d3558 | 179 | execvp(subcmd_config.exec_name, (char **)nargv); |
07800601 IM |
180 | |
181 | free(nargv); | |
182 | return -1; | |
183 | } | |
184 | ||
185 | ||
46113a54 | 186 | int execl_cmd(const char *cmd,...) |
07800601 IM |
187 | { |
188 | int argc; | |
189 | const char *argv[MAX_ARGS + 1]; | |
190 | const char *arg; | |
191 | va_list param; | |
192 | ||
193 | va_start(param, cmd); | |
194 | argv[0] = cmd; | |
195 | argc = 1; | |
196 | while (argc < MAX_ARGS) { | |
197 | arg = argv[argc++] = va_arg(param, char *); | |
198 | if (!arg) | |
199 | break; | |
200 | } | |
201 | va_end(param); | |
2f4ce5ec JP |
202 | if (MAX_ARGS <= argc) { |
203 | fprintf(stderr, " Error: too many args to run %s\n", cmd); | |
204 | return -1; | |
205 | } | |
07800601 IM |
206 | |
207 | argv[argc] = NULL; | |
46113a54 | 208 | return execv_cmd(argv); |
07800601 | 209 | } |