Adding upstream version 247.3.upstream/247.3upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 756 insertions, 0 deletions

diff --git a/src/basic/env-util.c b/src/basic/env-util.c
new file mode 100644
index 0000000..b2483af
--- /dev/null
+++ b/src/basic/env-util.c
@@ -0,0 +1,756 @@
+/* SPDX-License-Identifier: LGPL-2.1-or-later */
+
+#include <errno.h>
+#include <limits.h>
+#include <stdarg.h>
+#include <stdlib.h>
+#include <unistd.h>
+
+#include "alloc-util.h"
+#include "env-util.h"
+#include "escape.h"
+#include "extract-word.h"
+#include "macro.h"
+#include "parse-util.h"
+#include "string-util.h"
+#include "strv.h"
+#include "utf8.h"
+
+/* We follow bash for the character set. Different shells have different rules. */
+#define VALID_BASH_ENV_NAME_CHARS               \
+        DIGITS LETTERS                          \
+        "_"
+
+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 > (size_t) sysconf(_SC_ARG_MAX) - 2)
+                return false;
+
+        for (p = e; p < e + n; p++)
+                if (!strchr(VALID_BASH_ENV_NAME_CHARS, *p))
+                        return false;
+
+        return true;
+}
+
+bool env_name_is_valid(const char *e) {
+        return env_name_is_valid_n(e, strlen_ptr(e));
+}
+
+bool env_value_is_valid(const char *e) {
+        if (!e)
+                return false;
+
+        if (!utf8_is_valid(e))
+                return false;
+
+        /* Note that variable *values* may contain control characters, in particular NL, TAB, BS, DEL, ESC…
+         * When printing those variables with show-environment, we'll escape them. Make sure to print
+         * environment variables carefully! */
+
+        /* 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) > sc_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) > sc_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 assignments */
+                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;
+
+        STRV_FOREACH(p, l) {
+                if (!env_name_is_valid(*p))
+                        return false;
+
+                if (strv_contains(p + 1, *p))
+                        return false;
+        }
+
+        return true;
+}
+
+bool strv_env_name_or_assignment_is_valid(char **l) {
+        char **p;
+
+        STRV_FOREACH(p, l) {
+                if (!env_assignment_is_valid(*p) && !env_name_is_valid(*p))
+                        return false;
+
+                if (strv_contains(p + 1, *p))
+                        return false;
+        }
+
+        return true;
+}
+
+static int env_append(char **r, char ***k, char **a) {
+        assert(r);
+        assert(k);
+        assert(*k >= r);
+
+        if (!a)
+                return 0;
+
+        /* Expects the following arguments: 'r' shall point to the beginning of an strv we are going to append to, 'k'
+         * to a pointer pointing to the NULL entry at the end of the same array. 'a' shall point to another strv.
+         *
+         * This call adds every entry of 'a' to 'r', either overriding an existing matching entry, or appending to it.
+         *
+         * This call assumes 'r' has enough pre-allocated space to grow by all of 'a''s items. */
+
+        for (; *a; a++) {
+                char **j, *c;
+                size_t n;
+
+                n = strcspn(*a, "=");
+                if ((*a)[n] == '=')
+                        n++;
+
+                for (j = r; j < *k; j++)
+                        if (strneq(*j, *a, n))
+                                break;
+
+                c = strdup(*a);
+                if (!c)
+                        return -ENOMEM;
+
+                if (j >= *k) { /* Append to the end? */
+                        (*k)[0] = c;
+                        (*k)[1] = NULL;
+                        (*k)++;
+                } else
+                        free_and_replace(*j, c); /* Override existing item */
+        }
+
+        return 0;
+}
+
+char **strv_env_merge(size_t n_lists, ...) {
+        _cleanup_strv_free_ char **ret = NULL;
+        size_t n = 0, i;
+        char **l, **k;
+        va_list ap;
+
+        /* 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);
+
+        ret = new(char*, n+1);
+        if (!ret)
+                return NULL;
+
+        *ret = NULL;
+        k = ret;
+
+        va_start(ap, n_lists);
+        for (i = 0; i < n_lists; i++) {
+                l = va_arg(ap, char**);
+                if (env_append(ret, &k, l) < 0) {
+                        va_end(ap);
+                        return NULL;
+                }
+        }
+        va_end(ap);
+
+        return TAKE_PTR(ret);
+}
+
+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;
+}
+
+static bool env_entry_has_name(const char *entry, const char *name) {
+        const char *t;
+
+        assert(entry);
+        assert(name);
+
+        t = startswith(entry, name);
+        if (!t)
+                return false;
+
+        return *t == '=';
+}
+
+char **strv_env_delete(char **x, size_t 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) {
+                size_t 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;
+}
+
+int strv_env_replace(char ***l, char *p) {
+        const char *t, *name;
+        char **f;
+        int r;
+
+        assert(p);
+
+        /* Replace first occurrence of the env var or add a new one in the string list. Drop other occurrences. Edits
+         * in-place. Does not copy p.  p must be a valid key=value assignment.
+         */
+
+        t = strchr(p, '=');
+        if (!t)
+                return -EINVAL;
+
+        name = strndupa(p, t - p);
+
+        STRV_FOREACH(f, *l)
+                if (env_entry_has_name(*f, name)) {
+                        free_and_replace(*f, p);
+                        strv_env_unset(f + 1, *f);
+                        return 0;
+                }
+
+        /* We didn't find a match, we need to append p or create a new strv */
+        r = strv_push(l, p);
+        if (r < 0)
+                return r;
+
+        return 1;
+}
+
+char **strv_env_set(char **x, const char *p) {
+        _cleanup_strv_free_ char **ret = NULL;
+        size_t n, m;
+        char **k;
+
+        /* Overrides the env var setting of p, returns a new copy */
+
+        n = strv_length(x);
+        m = n + 2;
+        if (m < n) /* overflow? */
+                return NULL;
+
+        ret = new(char*, m);
+        if (!ret)
+                return NULL;
+
+        *ret = NULL;
+        k = ret;
+
+        if (env_append(ret, &k, x) < 0)
+                return NULL;
+
+        if (env_append(ret, &k, STRV_MAKE(p)) < 0)
+                return NULL;
+
+        return TAKE_PTR(ret);
+}
+
+char *strv_env_get_n(char **l, const char *name, size_t k, unsigned flags) {
+        char **i;
+
+        assert(name);
+
+        if (k <= 0)
+                return NULL;
+
+        STRV_FOREACH_BACKWARDS(i, l)
+                if (strneq(*i, name, k) &&
+                    (*i)[k] == '=')
+                        return *i + k + 1;
+
+        if (flags & REPLACE_ENV_USE_ENVIRONMENT) {
+                const char *t;
+
+                t = strndupa(name, k);
+                return getenv(t);
+        };
+
+        return NULL;
+}
+
+char *strv_env_get(char **l, const char *name) {
+        assert(name);
+
+        return strv_env_get_n(l, name, strlen(name), 0);
+}
+
+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_n(const char *format, size_t n, char **env, unsigned flags) {
+        enum {
+                WORD,
+                CURLY,
+                VARIABLE,
+                VARIABLE_RAW,
+                TEST,
+                DEFAULT_VALUE,
+                ALTERNATE_VALUE,
+        } state = WORD;
+
+        const char *e, *word = format, *test_value;
+        char *k;
+        _cleanup_free_ char *r = NULL;
+        size_t i, len;
+        int nest = 0;
+
+        assert(format);
+
+        for (e = format, i = 0; *e && i < n; e ++, i ++)
+                switch (state) {
+
+                case WORD:
+                        if (*e == '$')
+                                state = CURLY;
+                        break;
+
+                case CURLY:
+                        if (*e == '{') {
+                                k = strnappend(r, word, e-word-1);
+                                if (!k)
+                                        return NULL;
+
+                                free_and_replace(r, k);
+
+                                word = e-1;
+                                state = VARIABLE;
+                                nest++;
+                        } else if (*e == '$') {
+                                k = strnappend(r, word, e-word);
+                                if (!k)
+                                        return NULL;
+
+                                free_and_replace(r, k);
+
+                                word = e+1;
+                                state = WORD;
+
+                        } else if (flags & REPLACE_ENV_ALLOW_BRACELESS && strchr(VALID_BASH_ENV_NAME_CHARS, *e)) {
+                                k = strnappend(r, word, e-word-1);
+                                if (!k)
+                                        return NULL;
+
+                                free_and_replace(r, k);
+
+                                word = e-1;
+                                state = VARIABLE_RAW;
+
+                        } else
+                                state = WORD;
+                        break;
+
+                case VARIABLE:
+                        if (*e == '}') {
+                                const char *t;
+
+                                t = strv_env_get_n(env, word+2, e-word-2, flags);
+
+                                k = strjoin(r, t);
+                                if (!k)
+                                        return NULL;
+
+                                free_and_replace(r, k);
+
+                                word = e+1;
+                                state = WORD;
+                        } else if (*e == ':') {
+                                if (!(flags & REPLACE_ENV_ALLOW_EXTENDED))
+                                        /* Treat this as unsupported syntax, i.e. do no replacement */
+                                        state = WORD;
+                                else {
+                                        len = e-word-2;
+                                        state = TEST;
+                                }
+                        }
+                        break;
+
+                case TEST:
+                        if (*e == '-')
+                                state = DEFAULT_VALUE;
+                        else if (*e == '+')
+                                state = ALTERNATE_VALUE;
+                        else {
+                                state = WORD;
+                                break;
+                        }
+
+                        test_value = e+1;
+                        break;
+
+                case DEFAULT_VALUE: /* fall through */
+                case ALTERNATE_VALUE:
+                        assert(flags & REPLACE_ENV_ALLOW_EXTENDED);
+
+                        if (*e == '{') {
+                                nest++;
+                                break;
+                        }
+
+                        if (*e != '}')
+                                break;
+
+                        nest--;
+                        if (nest == 0) {
+                                const char *t;
+                                _cleanup_free_ char *v = NULL;
+
+                                t = strv_env_get_n(env, word+2, len, flags);
+
+                                if (t && state == ALTERNATE_VALUE)
+                                        t = v = replace_env_n(test_value, e-test_value, env, flags);
+                                else if (!t && state == DEFAULT_VALUE)
+                                        t = v = replace_env_n(test_value, e-test_value, env, flags);
+
+                                k = strjoin(r, t);
+                                if (!k)
+                                        return NULL;
+
+                                free_and_replace(r, k);
+
+                                word = e+1;
+                                state = WORD;
+                        }
+                        break;
+
+                case VARIABLE_RAW:
+                        assert(flags & REPLACE_ENV_ALLOW_BRACELESS);
+
+                        if (!strchr(VALID_BASH_ENV_NAME_CHARS, *e)) {
+                                const char *t;
+
+                                t = strv_env_get_n(env, word+1, e-word-1, flags);
+
+                                k = strjoin(r, t);
+                                if (!k)
+                                        return NULL;
+
+                                free_and_replace(r, k);
+
+                                word = e--;
+                                i--;
+                                state = WORD;
+                        }
+                        break;
+                }
+
+        if (state == VARIABLE_RAW) {
+                const char *t;
+
+                assert(flags & REPLACE_ENV_ALLOW_BRACELESS);
+
+                t = strv_env_get_n(env, word+1, e-word-1, flags);
+                return strjoin(r, t);
+        } else
+                return strnappend(r, word, e-word);
+}
+
+char **replace_env_argv(char **argv, char **env) {
+        char **ret, **i;
+        size_t k = 0, l = 0;
+
+        l = strv_length(argv);
+
+        ret = new(char*, l+1);
+        if (!ret)
+                return NULL;
+
+        STRV_FOREACH(i, argv) {
+
+                /* If $FOO appears as single word, replace it by the split up variable */
+                if ((*i)[0] == '$' && !IN_SET((*i)[1], '{', '$')) {
+                        char *e;
+                        char **w, **m = NULL;
+                        size_t q;
+
+                        e = strv_env_get(env, *i+1);
+                        if (e) {
+                                int r;
+
+                                r = strv_split_full(&m, e, WHITESPACE, EXTRACT_RELAX|EXTRACT_UNQUOTE);
+                                if (r < 0) {
+                                        ret[k] = NULL;
+                                        strv_free(ret);
+                                        return NULL;
+                                }
+                        } else
+                                m = NULL;
+
+                        q = strv_length(m);
+                        l = l + q - 1;
+
+                        w = reallocarray(ret, l + 1, sizeof(char *));
+                        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, 0);
+                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);
+}
+
+int getenv_bool_secure(const char *p) {
+        const char *e;
+
+        e = secure_getenv(p);
+        if (!e)
+                return -ENXIO;
+
+        return parse_boolean(e);
+}
+
+int set_unset_env(const char *name, const char *value, bool overwrite) {
+        int r;
+
+        if (value)
+                r = setenv(name, value, overwrite);
+        else
+                r = unsetenv(name);
+        if (r < 0)
+                return -errno;
+        return 0;
+}