+++ /dev/null
-/* -*-c-*-
- *
- * Fiddling with environment variables
- *
- * (c) 1999 Straylight/Edgeware
- */
-
-/*----- Licensing notice --------------------------------------------------*
- *
- * This file is part of the mLib utilities library.
- *
- * mLib is free software; you can redistribute it and/or modify
- * it under the terms of the GNU Library General Public License as
- * published by the Free Software Foundation; either version 2 of the
- * License, or (at your option) any later version.
- *
- * mLib 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 Library General Public License for more details.
- *
- * You should have received a copy of the GNU Library General Public
- * License along with mLib; if not, write to the Free
- * Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
- * MA 02111-1307, USA.
- */
-
-/*----- Header files ------------------------------------------------------*/
-
-#include <stdio.h>
-#include <stdlib.h>
-#include <string.h>
-
-#include "alloc.h"
-#include "sym.h"
-
-/*----- Data structures ---------------------------------------------------*/
-
-typedef struct var {
- sym_base _base;
- char *v;
-} var;
-
-/*----- Main code ---------------------------------------------------------*/
-
-/* --- @env_get@ --- *
- *
- * Arguments: @sym_table *t@ = pointer to a symbol table
- * @const char *name@ = pointer to variable name to look up
- *
- * Returns: Pointer to corresponding value string, or null.
- *
- * Use: Looks up an environment variable in the table and returns its
- * value. If the variable can't be found, a null pointer is
- * returned.
- */
-
-char *env_get(sym_table *t, const char *name)
-{
- var *e = sym_find(t, name, -1, 0, 0);
- return (e ? e->v : 0);
-}
-
-/* --- @env_put@ --- *
- *
- * Arguments: @sym_table *t@ = pointer to a symbol table
- * @const char *name@ = pointer to variable name to set
- * @const char *value@ = pointer to value string to assign
- *
- * Returns: ---
- *
- * Use: Assigns a value to a variable. If the @name@ contains an
- * equals character, then it's assumed to be of the form
- * `VAR=VALUE' and @value@ argument is ignored. Otherwise, if
- * @value@ is null, the variable is deleted. Finally, the
- * normal case: @name@ is a plain name, and @value@ is a normal
- * string causes the variable to be assigned the value in the
- * way you'd expect.
- */
-
-void env_put(sym_table *t, const char *name, const char *value)
-{
- char *q = 0;
-
- /* --- Sort out the mess with `NAME=VALUE' forms --- */
-
- {
- size_t eq = strcspn(name, "=");
- if (name[eq] == '=') {
- q = x_alloc(t->t.a, eq + 1);
- memcpy(q, name, eq);
- q[eq] = 0;
- value = name + eq + 1;
- name = q;
- }
- }
-
- /* --- Read the current value --- */
-
- if (!value) {
- var *v;
- if ((v = sym_find(t, name, -1, 0, 0)) != 0) {
- x_free(t->t.a, v->v);
- sym_remove(t, v);
- }
- } else {
- unsigned found;
- var *v = sym_find(t, name, -1, sizeof(*v), &found);
- if (found)
- x_free(t->t.a, v->v);
- v->v = x_strdup(t->t.a, value);
- }
-
- /* --- Tidying --- */
-
- if (q)
- xfree(q);
-}
-
-/* --- @env_import@ --- *
- *
- * Arguments: @sym_table *t@ = pointer to a symbol table
- * @char **env@ = pointer to an environment list
- *
- * Returns: ---
- *
- * Use: Inserts all of the environment variables listed into a symbol
- * table for rapid access. Equivalent to a lot of calls to
- * @env_put@.
- */
-
-void env_import(sym_table *t, char **env)
-{
- while (*env) {
- env_put(t, *env, 0);
- env++;
- }
-}
-
-/* --- @env_export@ --- *
- *
- * Arguments: @sym_table *t@ = pointer to a symbol table
- *
- * Returns: A big environment list.
- *
- * Use: Extracts an environment table from a symbol table
- * representation of an environment. The table and all of the
- * strings are in one big block allocated from the heap.
- */
-
-char **env_export(sym_table *t)
-{
- size_t n = 1;
- size_t sz = 0;
- sym_iter i;
- var *v;
- char **env;
- char *p, **pp;
-
- /* --- Work out sizes for everything --- */
-
- for (sym_mkiter(&i, t); (v = sym_next(&i)) != 0; ) {
- n++;
- sz += SYM_LEN(v) + strlen(v->v) + 2;
- }
-
- /* --- Allocate the big chunk of memory --- */
-
- env = pp = xmalloc(n * sizeof(char *) + sz);
- p = (char *)(env + n);
-
- /* --- Dump the output in the big chunk of memory --- */
-
- for (sym_mkiter(&i, t); (v = sym_next(&i)) != 0; ) {
- const char *name = SYM_NAME(v);
- size_t nlen = strlen(name), vlen = strlen(v->v);
- *pp++ = p;
- memcpy(p, name, nlen); p += nlen;
- *p++ = '=';
- memcpy(p, v->v, vlen); p += vlen;
- *p++ = 0;
- }
- *pp++ = 0;
- return (env);
-}
-
-/* --- @env_destroy@ --- *
- *
- * Arguments: @sym_table *t@ = pointer to symbol table
- *
- * Returns: ---
- *
- * Use: Destroys all the variables in the symbol table.
- */
-
-void env_destroy(sym_table *t)
-{
- sym_iter i;
- var *v;
-
- for (sym_mkiter(&i, t); (v = sym_next(&i)) != 0; )
- x_free(t->t.a, v->v);
- sym_destroy(t);
-}
-
-/*----- That's all, folks -------------------------------------------------*/
~mdw / mLib / blobdiff