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Diffstat (limited to 'src/unit-name.c')
-rw-r--r-- | src/unit-name.c | 424 |
1 files changed, 424 insertions, 0 deletions
diff --git a/src/unit-name.c b/src/unit-name.c new file mode 100644 index 0000000000..c5901cacfa --- /dev/null +++ b/src/unit-name.c @@ -0,0 +1,424 @@ +/*-*- Mode: C; c-basic-offset: 8 -*-*/ + +/*** + This file is part of systemd. + + Copyright 2010 Lennart Poettering + + systemd is free software; you can redistribute it and/or modify it + under the terms of the GNU General Public License as published by + the Free Software Foundation; either version 2 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 + General Public License for more details. + + You should have received a copy of the GNU General Public License + along with systemd; If not, see <http://www.gnu.org/licenses/>. +***/ + +#include <errno.h> +#include <string.h> + +#include "unit.h" +#include "unit-name.h" + +#define VALID_CHARS \ + "0123456789" \ + "abcdefghijklmnopqrstuvwxyz" \ + "ABCDEFGHIJKLMNOPQRSTUVWXYZ" \ + ":-_.\\" + +UnitType unit_name_to_type(const char *n) { + UnitType t; + + assert(n); + + for (t = 0; t < _UNIT_TYPE_MAX; t++) + if (endswith(n, unit_vtable[t]->suffix)) + return t; + + return _UNIT_TYPE_INVALID; +} + +bool unit_name_is_valid(const char *n) { + UnitType t; + const char *e, *i, *at; + + /* Valid formats: + * + * string@instance.suffix + * string.suffix + */ + + assert(n); + + if (strlen(n) >= UNIT_NAME_MAX) + return false; + + t = unit_name_to_type(n); + if (t < 0 || t >= _UNIT_TYPE_MAX) + return false; + + assert_se(e = strrchr(n, '.')); + + if (e == n) + return false; + + for (i = n, at = NULL; i < e; i++) { + + if (*i == '@' && !at) + at = i; + + if (!strchr("@" VALID_CHARS, *i)) + return false; + } + + if (at) { + if (at == n) + return false; + + if (at[1] == '.') + return false; + } + + return true; +} + +bool unit_instance_is_valid(const char *i) { + assert(i); + + /* The max length depends on the length of the string, so we + * don't really check this here. */ + + if (i[0] == 0) + return false; + + /* We allow additional @ in the instance string, we do not + * allow them in the prefix! */ + + for (; *i; i++) + if (!strchr("@" VALID_CHARS, *i)) + return false; + + return true; +} + +bool unit_prefix_is_valid(const char *p) { + + /* We don't allow additional @ in the instance string */ + + if (p[0] == 0) + return false; + + for (; *p; p++) + if (!strchr(VALID_CHARS, *p)) + return false; + + return true; +} + +int unit_name_to_instance(const char *n, char **instance) { + const char *p, *d; + char *i; + + assert(n); + assert(instance); + + /* Everything past the first @ and before the last . is the instance */ + if (!(p = strchr(n, '@'))) { + *instance = NULL; + return 0; + } + + assert_se(d = strrchr(n, '.')); + assert(p < d); + + if (!(i = strndup(p+1, d-p-1))) + return -ENOMEM; + + *instance = i; + return 0; +} + +char *unit_name_to_prefix_and_instance(const char *n) { + const char *d; + + assert(n); + + assert_se(d = strrchr(n, '.')); + + return strndup(n, d - n); +} + +char *unit_name_to_prefix(const char *n) { + const char *p; + + if ((p = strchr(n, '@'))) + return strndup(n, p - n); + + return unit_name_to_prefix_and_instance(n); +} + +char *unit_name_change_suffix(const char *n, const char *suffix) { + char *e, *r; + size_t a, b; + + assert(n); + assert(unit_name_is_valid(n)); + assert(suffix); + + assert_se(e = strrchr(n, '.')); + a = e - n; + b = strlen(suffix); + + if (!(r = new(char, a + b + 1))) + return NULL; + + memcpy(r, n, a); + memcpy(r+a, suffix, b+1); + + return r; +} + +char *unit_name_build(const char *prefix, const char *instance, const char *suffix) { + char *r; + + assert(prefix); + assert(unit_prefix_is_valid(prefix)); + assert(!instance || unit_instance_is_valid(instance)); + assert(suffix); + assert(unit_name_to_type(suffix) >= 0); + + if (!instance) + return strappend(prefix, suffix); + + if (asprintf(&r, "%s@%s%s", prefix, instance, suffix) < 0) + return NULL; + + return r; +} + +static char* do_escape(const char *f, char *t) { + assert(f); + assert(t); + + for (; *f; f++) { + if (*f == '/') + *(t++) = '-'; + else if (*f == '-' || *f == '\\' || !strchr(VALID_CHARS, *f)) { + *(t++) = '\\'; + *(t++) = 'x'; + *(t++) = hexchar(*f > 4); + *(t++) = hexchar(*f); + } else + *(t++) = *f; + } + + return t; +} + +char *unit_name_build_escape(const char *prefix, const char *instance, const char *suffix) { + char *r, *t; + size_t a, b, c; + + assert(prefix); + assert(suffix); + assert(unit_name_to_type(suffix) >= 0); + + /* Takes a arbitrary string for prefix and instance plus a + * suffix and makes a nice string suitable as unit name of it, + * escaping all weird chars on the way. + * + * / becomes ., and all chars not alloweed in a unit name get + * escaped as \xFF, including \ and ., of course. This + * escaping is hence reversible. + * + * This is primarily useful to make nice unit names from + * strings, but is actually useful for any kind of string. + */ + + a = strlen(prefix); + c = strlen(suffix); + + if (instance) { + b = strlen(instance); + + if (!(r = new(char, a*4 + 1 + b*4 + c + 1))) + return NULL; + + t = do_escape(prefix, r); + *(t++) = '@'; + t = do_escape(instance, t); + } else { + + if (!(r = new(char, a*4 + c + 1))) + return NULL; + + t = do_escape(prefix, r); + } + + strcpy(t, suffix); + return r; +} + +char *unit_name_escape(const char *f) { + char *r, *t; + + if (!(r = new(char, strlen(f)*4+1))) + return NULL; + + t = do_escape(f, r); + *t = 0; + + return r; + +} + +char *unit_name_unescape(const char *f) { + char *r, *t; + + assert(f); + + if (!(r = strdup(f))) + return NULL; + + for (t = r; *f; f++) { + if (*f == '-') + *(t++) = '/'; + else if (*f == '\\') { + int a, b; + + if ((a = unhexchar(f[1])) < 0 || + (b = unhexchar(f[2])) < 0) { + /* Invalid escape code, let's take it literal then */ + *(t++) = '\\'; + } else { + *(t++) = (char) ((a << 4) | b); + f += 2; + } + } else + *(t++) = *f; + } + + *t = 0; + + return r; +} + +bool unit_name_is_template(const char *n) { + const char *p; + + assert(n); + + if (!(p = strchr(n, '@'))) + return false; + + return p[1] == '.'; +} + +char *unit_name_replace_instance(const char *f, const char *i) { + const char *p, *e; + char *r, *k; + size_t a; + + assert(f); + + p = strchr(f, '@'); + assert_se(e = strrchr(f, '.')); + + a = p - f; + + if (p) { + size_t b; + + b = strlen(i); + + if (!(r = new(char, a + 1 + b + strlen(e) + 1))) + return NULL; + + k = mempcpy(r, f, a + 1); + k = mempcpy(k, i, b); + } else { + + if (!(r = new(char, a + strlen(e) + 1))) + return NULL; + + k = mempcpy(r, f, a); + } + + strcpy(k, e); + return r; +} + +char *unit_name_template(const char *f) { + const char *p, *e; + char *r; + size_t a; + + if (!(p = strchr(f, '@'))) + return strdup(f); + + assert_se(e = strrchr(f, '.')); + a = p - f + 1; + + if (!(r = new(char, a + strlen(e) + 1))) + return NULL; + + strcpy(mempcpy(r, f, a), e); + return r; + +} + +char *unit_name_from_path(const char *path, const char *suffix) { + char *p, *r; + + assert(path); + assert(suffix); + + if (!(p = strdup(path))) + return NULL; + + path_kill_slashes(p); + + path = p[0] == '/' ? p + 1 : p; + + if (path[0] == 0) { + free(p); + return strappend("-", suffix); + } + + r = unit_name_build_escape(path, NULL, suffix); + free(p); + + return r; +} + +char *unit_name_to_path(const char *name) { + char *w, *e; + + assert(name); + + if (!(w = unit_name_to_prefix(name))) + return NULL; + + e = unit_name_unescape(w); + free(w); + + if (!e) + return NULL; + + if (e[0] != '/') { + w = strappend("/", e); + free(e); + + if (!w) + return NULL; + + e = w; + } + + return e; +} |