util-lib: move string table stuff into its own string-table.[ch]

1 files changed, 88 insertions, 0 deletions

diff --git a/src/basic/string-table.h b/src/basic/string-table.h
new file mode 100644
index 0000000000..51b6007214
--- /dev/null
+++ b/src/basic/string-table.h
@@ -0,0 +1,88 @@
+
+/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
+
+#pragma once
+
+/***
+  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 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 <stddef.h>
+#include <stdio.h>
+#include <string.h>
+#include <sys/types.h>
+
+#include "macro.h"
+#include "parse-util.h"
+#include "string-util.h"
+
+ssize_t string_table_lookup(const char * const *table, size_t len, const char *key);
+
+/* For basic lookup tables with strictly enumerated entries */
+#define _DEFINE_STRING_TABLE_LOOKUP_TO_STRING(name,type,scope)          \
+        scope const char *name##_to_string(type i) {                    \
+                if (i < 0 || i >= (type) ELEMENTSOF(name##_table))      \
+                        return NULL;                                    \
+                return name##_table[i];                                 \
+        }
+
+#define _DEFINE_STRING_TABLE_LOOKUP_FROM_STRING(name,type,scope)        \
+        scope type name##_from_string(const char *s) {                  \
+                return (type) string_table_lookup(name##_table, ELEMENTSOF(name##_table), s); \
+        }
+
+#define _DEFINE_STRING_TABLE_LOOKUP(name,type,scope)                    \
+        _DEFINE_STRING_TABLE_LOOKUP_TO_STRING(name,type,scope)          \
+        _DEFINE_STRING_TABLE_LOOKUP_FROM_STRING(name,type,scope)        \
+        struct __useless_struct_to_allow_trailing_semicolon__
+
+#define DEFINE_STRING_TABLE_LOOKUP(name,type) _DEFINE_STRING_TABLE_LOOKUP(name,type,)
+#define DEFINE_PRIVATE_STRING_TABLE_LOOKUP(name,type) _DEFINE_STRING_TABLE_LOOKUP(name,type,static)
+#define DEFINE_PRIVATE_STRING_TABLE_LOOKUP_TO_STRING(name,type) _DEFINE_STRING_TABLE_LOOKUP_TO_STRING(name,type,static)
+#define DEFINE_PRIVATE_STRING_TABLE_LOOKUP_FROM_STRING(name,type) _DEFINE_STRING_TABLE_LOOKUP_FROM_STRING(name,type,static)
+
+/* For string conversions where numbers are also acceptable */
+#define DEFINE_STRING_TABLE_LOOKUP_WITH_FALLBACK(name,type,max)         \
+        int name##_to_string_alloc(type i, char **str) {                \
+                char *s;                                                \
+                if (i < 0 || i > max)                                   \
+                        return -ERANGE;                                 \
+                if (i < (type) ELEMENTSOF(name##_table)) {              \
+                        s = strdup(name##_table[i]);                    \
+                        if (!s)                                         \
+                                return -ENOMEM;                         \
+                } else {                                                \
+                        if (asprintf(&s, "%i", i) < 0)                  \
+                                return -ENOMEM;                         \
+                }                                                       \
+                *str = s;                                               \
+                return 0;                                               \
+        }                                                               \
+        type name##_from_string(const char *s) {                        \
+                type i;                                                 \
+                unsigned u = 0;                                         \
+                if (!s)                                                 \
+                        return (type) -1;                               \
+                for (i = 0; i < (type) ELEMENTSOF(name##_table); i++)   \
+                        if (streq_ptr(name##_table[i], s))              \
+                                return i;                               \
+                if (safe_atou(s, &u) >= 0 && u <= max)                  \
+                        return (type) u;                                \
+                return (type) -1;                                       \
+        }                                                               \
+        struct __useless_struct_to_allow_trailing_semicolon__