| /*** |
| This file is part of systemd. |
| |
| Copyright 2012 Lennart Poettering |
| |
| systemd is free software; you can redistribute it and/or modify it |
| under the terms of the GNU Lesser General Public License as published by |
| the Free Software Foundation; either version 2.1 of the License, or |
| (at your option) any later version. |
| |
| systemd is distributed in the hope that it will be useful, but |
| WITHOUT ANY WARRANTY; without even the implied warranty of |
| MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| Lesser General Public License for more details. |
| |
| You should have received a copy of the GNU Lesser General Public License |
| along with systemd; If not, see <http://www.gnu.org/licenses/>. |
| ***/ |
| |
| #include <errno.h> |
| #include <limits.h> |
| #include <stdarg.h> |
| #include <stdlib.h> |
| #include <string.h> |
| #include <unistd.h> |
| |
| #include "alloc-util.h" |
| #include "env-util.h" |
| #include "extract-word.h" |
| #include "macro.h" |
| #include "parse-util.h" |
| #include "string-util.h" |
| #include "strv.h" |
| #include "utf8.h" |
| |
| #define VALID_CHARS_ENV_NAME \ |
| DIGITS LETTERS \ |
| "_" |
| |
| #ifndef ARG_MAX |
| #define ARG_MAX ((size_t) sysconf(_SC_ARG_MAX)) |
| #endif |
| |
| static bool env_name_is_valid_n(const char *e, size_t n) { |
| const char *p; |
| |
| if (!e) |
| return false; |
| |
| if (n <= 0) |
| return false; |
| |
| if (e[0] >= '0' && e[0] <= '9') |
| return false; |
| |
| /* POSIX says the overall size of the environment block cannot |
| * be > ARG_MAX, an individual assignment hence cannot be |
| * either. Discounting the equal sign and trailing NUL this |
| * hence leaves ARG_MAX-2 as longest possible variable |
| * name. */ |
| if (n > ARG_MAX - 2) |
| return false; |
| |
| for (p = e; p < e + n; p++) |
| if (!strchr(VALID_CHARS_ENV_NAME, *p)) |
| return false; |
| |
| return true; |
| } |
| |
| bool env_name_is_valid(const char *e) { |
| if (!e) |
| return false; |
| |
| return env_name_is_valid_n(e, strlen(e)); |
| } |
| |
| bool env_value_is_valid(const char *e) { |
| if (!e) |
| return false; |
| |
| if (!utf8_is_valid(e)) |
| return false; |
| |
| /* bash allows tabs in environment variables, and so should |
| * we */ |
| if (string_has_cc(e, "\t")) |
| return false; |
| |
| /* POSIX says the overall size of the environment block cannot |
| * be > ARG_MAX, an individual assignment hence cannot be |
| * either. Discounting the shortest possible variable name of |
| * length 1, the equal sign and trailing NUL this hence leaves |
| * ARG_MAX-3 as longest possible variable value. */ |
| if (strlen(e) > ARG_MAX - 3) |
| return false; |
| |
| return true; |
| } |
| |
| bool env_assignment_is_valid(const char *e) { |
| const char *eq; |
| |
| eq = strchr(e, '='); |
| if (!eq) |
| return false; |
| |
| if (!env_name_is_valid_n(e, eq - e)) |
| return false; |
| |
| if (!env_value_is_valid(eq + 1)) |
| return false; |
| |
| /* POSIX says the overall size of the environment block cannot |
| * be > ARG_MAX, hence the individual variable assignments |
| * cannot be either, but let's leave room for one trailing NUL |
| * byte. */ |
| if (strlen(e) > ARG_MAX - 1) |
| return false; |
| |
| return true; |
| } |
| |
| bool strv_env_is_valid(char **e) { |
| char **p, **q; |
| |
| STRV_FOREACH(p, e) { |
| size_t k; |
| |
| if (!env_assignment_is_valid(*p)) |
| return false; |
| |
| /* Check if there are duplicate assginments */ |
| k = strcspn(*p, "="); |
| STRV_FOREACH(q, p + 1) |
| if (strneq(*p, *q, k) && (*q)[k] == '=') |
| return false; |
| } |
| |
| return true; |
| } |
| |
| bool strv_env_name_is_valid(char **l) { |
| char **p, **q; |
| |
| STRV_FOREACH(p, l) { |
| if (!env_name_is_valid(*p)) |
| return false; |
| |
| STRV_FOREACH(q, p + 1) |
| if (streq(*p, *q)) |
| return false; |
| } |
| |
| return true; |
| } |
| |
| bool strv_env_name_or_assignment_is_valid(char **l) { |
| char **p, **q; |
| |
| STRV_FOREACH(p, l) { |
| if (!env_assignment_is_valid(*p) && !env_name_is_valid(*p)) |
| return false; |
| |
| STRV_FOREACH(q, p + 1) |
| if (streq(*p, *q)) |
| return false; |
| } |
| |
| return true; |
| } |
| |
| static int env_append(char **r, char ***k, char **a) { |
| assert(r); |
| assert(k); |
| |
| if (!a) |
| return 0; |
| |
| /* Add the entries of a to *k unless they already exist in *r |
| * in which case they are overridden instead. This assumes |
| * there is enough space in the r array. */ |
| |
| for (; *a; a++) { |
| char **j; |
| size_t n; |
| |
| n = strcspn(*a, "="); |
| |
| if ((*a)[n] == '=') |
| n++; |
| |
| for (j = r; j < *k; j++) |
| if (strneq(*j, *a, n)) |
| break; |
| |
| if (j >= *k) |
| (*k)++; |
| else |
| free(*j); |
| |
| *j = strdup(*a); |
| if (!*j) |
| return -ENOMEM; |
| } |
| |
| return 0; |
| } |
| |
| char **strv_env_merge(unsigned n_lists, ...) { |
| size_t n = 0; |
| char **l, **k, **r; |
| va_list ap; |
| unsigned i; |
| |
| /* Merges an arbitrary number of environment sets */ |
| |
| va_start(ap, n_lists); |
| for (i = 0; i < n_lists; i++) { |
| l = va_arg(ap, char**); |
| n += strv_length(l); |
| } |
| va_end(ap); |
| |
| r = new(char*, n+1); |
| if (!r) |
| return NULL; |
| |
| k = r; |
| |
| va_start(ap, n_lists); |
| for (i = 0; i < n_lists; i++) { |
| l = va_arg(ap, char**); |
| if (env_append(r, &k, l) < 0) |
| goto fail; |
| } |
| va_end(ap); |
| |
| *k = NULL; |
| |
| return r; |
| |
| fail: |
| va_end(ap); |
| strv_free(r); |
| |
| return NULL; |
| } |
| |
| _pure_ static bool env_match(const char *t, const char *pattern) { |
| assert(t); |
| assert(pattern); |
| |
| /* pattern a matches string a |
| * a matches a= |
| * a matches a=b |
| * a= matches a= |
| * a=b matches a=b |
| * a= does not match a |
| * a=b does not match a= |
| * a=b does not match a |
| * a=b does not match a=c */ |
| |
| if (streq(t, pattern)) |
| return true; |
| |
| if (!strchr(pattern, '=')) { |
| size_t l = strlen(pattern); |
| |
| return strneq(t, pattern, l) && t[l] == '='; |
| } |
| |
| return false; |
| } |
| |
| char **strv_env_delete(char **x, unsigned n_lists, ...) { |
| size_t n, i = 0; |
| char **k, **r; |
| va_list ap; |
| |
| /* Deletes every entry from x that is mentioned in the other |
| * string lists */ |
| |
| n = strv_length(x); |
| |
| r = new(char*, n+1); |
| if (!r) |
| return NULL; |
| |
| STRV_FOREACH(k, x) { |
| unsigned v; |
| |
| va_start(ap, n_lists); |
| for (v = 0; v < n_lists; v++) { |
| char **l, **j; |
| |
| l = va_arg(ap, char**); |
| STRV_FOREACH(j, l) |
| if (env_match(*k, *j)) |
| goto skip; |
| } |
| va_end(ap); |
| |
| r[i] = strdup(*k); |
| if (!r[i]) { |
| strv_free(r); |
| return NULL; |
| } |
| |
| i++; |
| continue; |
| |
| skip: |
| va_end(ap); |
| } |
| |
| r[i] = NULL; |
| |
| assert(i <= n); |
| |
| return r; |
| } |
| |
| char **strv_env_unset(char **l, const char *p) { |
| |
| char **f, **t; |
| |
| if (!l) |
| return NULL; |
| |
| assert(p); |
| |
| /* Drops every occurrence of the env var setting p in the |
| * string list. Edits in-place. */ |
| |
| for (f = t = l; *f; f++) { |
| |
| if (env_match(*f, p)) { |
| free(*f); |
| continue; |
| } |
| |
| *(t++) = *f; |
| } |
| |
| *t = NULL; |
| return l; |
| } |
| |
| char **strv_env_unset_many(char **l, ...) { |
| |
| char **f, **t; |
| |
| if (!l) |
| return NULL; |
| |
| /* Like strv_env_unset() but applies many at once. Edits in-place. */ |
| |
| for (f = t = l; *f; f++) { |
| bool found = false; |
| const char *p; |
| va_list ap; |
| |
| va_start(ap, l); |
| |
| while ((p = va_arg(ap, const char*))) { |
| if (env_match(*f, p)) { |
| found = true; |
| break; |
| } |
| } |
| |
| va_end(ap); |
| |
| if (found) { |
| free(*f); |
| continue; |
| } |
| |
| *(t++) = *f; |
| } |
| |
| *t = NULL; |
| return l; |
| } |
| |
| char **strv_env_set(char **x, const char *p) { |
| |
| char **k, **r; |
| char* m[2] = { (char*) p, NULL }; |
| |
| /* Overrides the env var setting of p, returns a new copy */ |
| |
| r = new(char*, strv_length(x)+2); |
| if (!r) |
| return NULL; |
| |
| k = r; |
| if (env_append(r, &k, x) < 0) |
| goto fail; |
| |
| if (env_append(r, &k, m) < 0) |
| goto fail; |
| |
| *k = NULL; |
| |
| return r; |
| |
| fail: |
| strv_free(r); |
| return NULL; |
| } |
| |
| char *strv_env_get_n(char **l, const char *name, size_t k) { |
| char **i; |
| |
| assert(name); |
| |
| if (k <= 0) |
| return NULL; |
| |
| STRV_FOREACH(i, l) |
| if (strneq(*i, name, k) && |
| (*i)[k] == '=') |
| return *i + k + 1; |
| |
| return NULL; |
| } |
| |
| char *strv_env_get(char **l, const char *name) { |
| assert(name); |
| |
| return strv_env_get_n(l, name, strlen(name)); |
| } |
| |
| char **strv_env_clean_with_callback(char **e, void (*invalid_callback)(const char *p, void *userdata), void *userdata) { |
| char **p, **q; |
| int k = 0; |
| |
| STRV_FOREACH(p, e) { |
| size_t n; |
| bool duplicate = false; |
| |
| if (!env_assignment_is_valid(*p)) { |
| if (invalid_callback) |
| invalid_callback(*p, userdata); |
| free(*p); |
| continue; |
| } |
| |
| n = strcspn(*p, "="); |
| STRV_FOREACH(q, p + 1) |
| if (strneq(*p, *q, n) && (*q)[n] == '=') { |
| duplicate = true; |
| break; |
| } |
| |
| if (duplicate) { |
| free(*p); |
| continue; |
| } |
| |
| e[k++] = *p; |
| } |
| |
| if (e) |
| e[k] = NULL; |
| |
| return e; |
| } |
| |
| char *replace_env(const char *format, char **env) { |
| enum { |
| WORD, |
| CURLY, |
| VARIABLE |
| } state = WORD; |
| |
| const char *e, *word = format; |
| char *r = NULL, *k; |
| |
| assert(format); |
| |
| for (e = format; *e; e ++) { |
| |
| switch (state) { |
| |
| case WORD: |
| if (*e == '$') |
| state = CURLY; |
| break; |
| |
| case CURLY: |
| if (*e == '{') { |
| k = strnappend(r, word, e-word-1); |
| if (!k) |
| goto fail; |
| |
| free(r); |
| r = k; |
| |
| word = e-1; |
| state = VARIABLE; |
| |
| } else if (*e == '$') { |
| k = strnappend(r, word, e-word); |
| if (!k) |
| goto fail; |
| |
| free(r); |
| r = k; |
| |
| word = e+1; |
| state = WORD; |
| } else |
| state = WORD; |
| break; |
| |
| case VARIABLE: |
| if (*e == '}') { |
| const char *t; |
| |
| t = strempty(strv_env_get_n(env, word+2, e-word-2)); |
| |
| k = strappend(r, t); |
| if (!k) |
| goto fail; |
| |
| free(r); |
| r = k; |
| |
| word = e+1; |
| state = WORD; |
| } |
| break; |
| } |
| } |
| |
| k = strnappend(r, word, e-word); |
| if (!k) |
| goto fail; |
| |
| free(r); |
| return k; |
| |
| fail: |
| free(r); |
| return NULL; |
| } |
| |
| char **replace_env_argv(char **argv, char **env) { |
| char **ret, **i; |
| unsigned k = 0, l = 0; |
| |
| l = strv_length(argv); |
| |
| ret = new(char*, l+1); |
| if (!ret) |
| return NULL; |
| |
| STRV_FOREACH(i, argv) { |
| |
| /* If $FOO appears as single word, replace it by the split up variable */ |
| if ((*i)[0] == '$' && (*i)[1] != '{' && (*i)[1] != '$') { |
| char *e; |
| char **w, **m = NULL; |
| unsigned q; |
| |
| e = strv_env_get(env, *i+1); |
| if (e) { |
| int r; |
| |
| r = strv_split_extract(&m, e, WHITESPACE, EXTRACT_RELAX|EXTRACT_QUOTES); |
| if (r < 0) { |
| ret[k] = NULL; |
| strv_free(ret); |
| return NULL; |
| } |
| } else |
| m = NULL; |
| |
| q = strv_length(m); |
| l = l + q - 1; |
| |
| w = realloc(ret, sizeof(char*) * (l+1)); |
| if (!w) { |
| ret[k] = NULL; |
| strv_free(ret); |
| strv_free(m); |
| return NULL; |
| } |
| |
| ret = w; |
| if (m) { |
| memcpy(ret + k, m, q * sizeof(char*)); |
| free(m); |
| } |
| |
| k += q; |
| continue; |
| } |
| |
| /* If ${FOO} appears as part of a word, replace it by the variable as-is */ |
| ret[k] = replace_env(*i, env); |
| if (!ret[k]) { |
| strv_free(ret); |
| return NULL; |
| } |
| k++; |
| } |
| |
| ret[k] = NULL; |
| return ret; |
| } |
| |
| int getenv_bool(const char *p) { |
| const char *e; |
| |
| e = getenv(p); |
| if (!e) |
| return -ENXIO; |
| |
| return parse_boolean(e); |
| } |