1 /* ====================================================================
2 * Copyright (c) 1995-1998 The Apache Group. All rights reserved.
4 * Redistribution and use in source and binary forms, with or without
5 * modification, are permitted provided that the following conditions
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 * notice, this list of conditions and the following disclaimer in
13 * the documentation and/or other materials provided with the
16 * 3. All advertising materials mentioning features or use of this
17 * software must display the following acknowledgment:
18 * "This product includes software developed by the Apache Group
19 * for use in the Apache HTTP server project (http://www.apache.org/)."
21 * 4. The names "Apache Server" and "Apache Group" must not be used to
22 * endorse or promote products derived from this software without
23 * prior written permission. For written permission, please contact
26 * 5. Products derived from this software may not be called "Apache"
27 * nor may "Apache" appear in their names without prior written
28 * permission of the Apache Group.
30 * 6. Redistributions of any form whatsoever must retain the following
32 * "This product includes software developed by the Apache Group
33 * for use in the Apache HTTP server project (http://www.apache.org/)."
35 * THIS SOFTWARE IS PROVIDED BY THE APACHE GROUP ``AS IS'' AND ANY
36 * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
37 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
38 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE APACHE GROUP OR
39 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
40 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
41 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
42 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
43 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
44 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
45 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
46 * OF THE POSSIBILITY OF SUCH DAMAGE.
47 * ====================================================================
49 * This software consists of voluntary contributions made by many
50 * individuals on behalf of the Apache Group and was originally based
51 * on public domain software written at the National Center for
52 * Supercomputing Applications, University of Illinois, Urbana-Champaign.
53 * For more information on the Apache Group and the Apache HTTP server
54 * project, please see <http://www.apache.org/>.
58 #ifndef APACHE_ALLOC_H
59 #define APACHE_ALLOC_H
66 * Resource allocation routines...
68 * designed so that we don't have to keep track of EVERYTHING so that
69 * it can be explicitly freed later (a fundamentally unsound strategy ---
70 * particularly in the presence of die()).
72 * Instead, we maintain pools, and allocate items (both memory and I/O
73 * handlers) from the pools --- currently there are two, one for per
74 * transaction info, and one for config info. When a transaction is over,
75 * we can delete everything in the per-transaction pool without fear, and
76 * without thinking too hard about it either.
81 /* Arenas for configuration info and transaction info
82 * --- actual layout of the pool structure is private to
86 /* Need declaration of DIR on Win32 */
88 #include "../os/win32/readdir.h"
91 typedef struct pool pool;
92 typedef struct pool ap_pool;
94 pool * ap_init_alloc(void); /* Set up everything */
95 API_EXPORT(pool *) ap_make_sub_pool(pool *); /* All pools are subpools of permanent_pool */
96 API_EXPORT(void) ap_destroy_pool(pool *);
98 /* used to guarantee to the pool debugging code that the sub pool will not be
99 * destroyed before the parent pool
105 #define ap_pool_join(a,b)
107 API_EXPORT(void) ap_pool_join(pool *p, pool *sub);
108 API_EXPORT(pool *) ap_find_pool(const void *ts);
109 API_EXPORT(int) ap_pool_is_ancestor(pool *a, pool *b);
112 /* Clearing out EVERYTHING in an pool... destroys any sub-pools */
114 API_EXPORT(void) ap_clear_pool(struct pool *);
116 /* Preparing for exec() --- close files, etc., but *don't* flush I/O
117 * buffers, *don't* wait for subprocesses, and *don't* free any memory.
120 API_EXPORT(void) ap_cleanup_for_exec(void);
122 /* routines to allocate memory from an pool... */
124 API_EXPORT(void *) ap_palloc(struct pool *, int nbytes);
125 API_EXPORT(void *) ap_pcalloc(struct pool *, int nbytes);
126 API_EXPORT(char *) ap_pstrdup(struct pool *, const char *s);
127 /* make a nul terminated copy of the n characters starting with s */
128 API_EXPORT(char *) ap_pstrndup(struct pool *, const char *s, int n);
129 API_EXPORT_NONSTD(char *) ap_pstrcat(struct pool *,...); /* all '...' must be char* */
130 API_EXPORT_NONSTD(char *) ap_psprintf(struct pool *, const char *fmt, ...)
131 __attribute__((format(printf,2,3)));
132 API_EXPORT(char *) ap_pvsprintf(struct pool *, const char *fmt, va_list);
134 /* array and alist management... keeping lists of things.
135 * Common enough to want common support code ...
146 API_EXPORT(array_header *) ap_make_array(pool *p, int nelts, int elt_size);
147 API_EXPORT(void *) ap_push_array(array_header *);
148 API_EXPORT(void) ap_array_cat(array_header *dst, const array_header *src);
149 API_EXPORT(array_header *) ap_append_arrays(pool *, const array_header *,
150 const array_header *);
152 /* copy_array copies the *entire* array. copy_array_hdr just copies
153 * the header, and arranges for the elements to be copied if (and only
154 * if) the code subsequently does a push or arraycat.
157 API_EXPORT(array_header *) ap_copy_array(pool *p, const array_header *src);
158 API_EXPORT(array_header *) ap_copy_array_hdr(pool *p, const array_header *src);
161 /* Tables. Implemented alist style, for now, though we try to keep
162 * it so that imposing a hash table structure on top in the future
163 * wouldn't be *too* hard...
165 * Note that key comparisons for these are case-insensitive, largely
166 * because that's what's appropriate and convenient everywhere they're
167 * currently being used...
170 typedef struct table table;
173 char *key; /* maybe NULL in future;
174 * check when iterating thru table_elts
179 API_EXPORT(table *) ap_make_table(pool *p, int nelts);
180 API_EXPORT(table *) ap_copy_table(pool *p, const table *);
181 API_EXPORT(void) ap_clear_table(table *);
182 API_EXPORT(const char *) ap_table_get(const table *, const char *);
183 API_EXPORT(void) ap_table_set(table *, const char *name, const char *val);
184 API_EXPORT(void) ap_table_setn(table *, const char *name, const char *val);
185 API_EXPORT(void) ap_table_merge(table *, const char *name, const char *more_val);
186 API_EXPORT(void) ap_table_mergen(table *, const char *name, const char *more_val);
187 API_EXPORT(void) ap_table_unset(table *, const char *key);
188 API_EXPORT(void) ap_table_add(table *, const char *name, const char *val);
189 API_EXPORT(void) ap_table_addn(table *, const char *name, const char *val);
190 API_EXPORT(void) ap_table_do(int (*comp) (void *, const char *, const char *), void *rec,
193 API_EXPORT(table *) ap_overlay_tables(pool *p, const table *overlay, const table *base);
195 /* XXX: these know about the definition of struct table in alloc.c. That
196 * definition is not here because it is supposed to be private, and by not
197 * placing it here we are able to get compile-time diagnostics from modules
198 * written which assume that a table is the same as an array_header. -djg
200 #define ap_table_elts(t) ((array_header *)(t))
201 #define ap_is_empty_table(t) (((t) == NULL)||(((array_header *)(t))->nelts == 0))
203 /* routines to remember allocation of other sorts of things...
204 * generic interface first. Note that we want to have two separate
205 * cleanup functions in the general case, one for exec() preparation,
206 * to keep CGI scripts and the like from inheriting access to things
207 * they shouldn't be able to touch, and one for actually cleaning up,
208 * when the actual server process wants to get rid of the thing,
211 * kill_cleanup disarms a cleanup, presumably because the resource in
212 * question has been closed, freed, or whatever, and it's scarce
213 * enough to want to reclaim (e.g., descriptors). It arranges for the
214 * resource not to be cleaned up a second time (it might have been
215 * reallocated). run_cleanup does the same, but runs it first.
217 * Cleanups are identified for purposes of finding & running them off by the
218 * plain_cleanup and data, which should presumably be unique.
220 * NB any code which invokes register_cleanup or kill_cleanup directly
221 * is a critical section which should be guarded by block_alarms() and
222 * unblock_alarms() below...
225 API_EXPORT(void) ap_register_cleanup(pool *p, void *data,
226 void (*plain_cleanup) (void *),
227 void (*child_cleanup) (void *));
229 API_EXPORT(void) ap_kill_cleanup(pool *p, void *data, void (*plain_cleanup) (void *));
230 API_EXPORT(void) ap_run_cleanup(pool *p, void *data, void (*cleanup) (void *));
232 /* A "do-nothing" cleanup, for register_cleanup; it's faster to do
233 * things this way than to test for NULL. */
234 API_EXPORT_NONSTD(void) ap_null_cleanup(void *data);
236 /* The time between when a resource is actually allocated, and when it
237 * its cleanup is registered is a critical section, during which the
238 * resource could leak if we got interrupted or timed out. So, anything
239 * which registers cleanups should bracket resource allocation and the
240 * cleanup registry with these. (This is done internally by run_cleanup).
242 * NB they are actually implemented in http_main.c, since they are bound
243 * up with timeout handling in general...
246 API_EXPORT(void) ap_block_alarms(void);
247 API_EXPORT(void) ap_unblock_alarms(void);
249 /* Common cases which want utility support..
250 * the note_cleanups_for_foo routines are for
253 API_EXPORT(FILE *) ap_pfopen(struct pool *, const char *name, const char *fmode);
254 API_EXPORT(FILE *) ap_pfdopen(struct pool *, int fd, const char *fmode);
255 API_EXPORT(int) ap_popenf(struct pool *, const char *name, int flg, int mode);
257 API_EXPORT(void) ap_note_cleanups_for_file(pool *, FILE *);
258 API_EXPORT(void) ap_note_cleanups_for_fd(pool *, int);
260 API_EXPORT(void) ap_note_cleanups_for_h(pool *, HANDLE);
262 API_EXPORT(void) ap_kill_cleanups_for_fd(pool *p, int fd);
264 API_EXPORT(void) ap_note_cleanups_for_socket(pool *, int);
265 API_EXPORT(void) ap_kill_cleanups_for_socket(pool *p, int sock);
266 API_EXPORT(int) ap_psocket(pool *p, int, int, int);
267 API_EXPORT(int) ap_pclosesocket(pool *a, int sock);
269 API_EXPORT(regex_t *) ap_pregcomp(pool *p, const char *pattern, int cflags);
270 API_EXPORT(void) ap_pregfree(pool *p, regex_t * reg);
272 /* routines to note closes... file descriptors are constrained enough
273 * on some systems that we want to support this.
276 API_EXPORT(int) ap_pfclose(struct pool *, FILE *);
277 API_EXPORT(int) ap_pclosef(struct pool *, int fd);
279 API_EXPORT(int) ap_pcloseh(struct pool *, HANDLE hDevice);
282 /* routines to deal with directories */
283 API_EXPORT(DIR *) ap_popendir(pool *p, const char *name);
284 API_EXPORT(void) ap_pclosedir(pool *p, DIR * d);
286 /* ... even child processes (which we may want to wait for,
287 * or to kill outright, on unexpected termination).
289 * ap_spawn_child is a utility routine which handles an awful lot of
290 * the rigamarole associated with spawning a child --- it arranges
291 * for pipes to the child's stdin and stdout, if desired (if not,
292 * set the associated args to NULL). It takes as args a function
293 * to call in the child, and an argument to be passed to the function.
296 enum kill_conditions {
297 kill_never, /* process is never sent any signals */
298 kill_always, /* process is sent SIGKILL on pool cleanup */
299 kill_after_timeout, /* SIGTERM, wait 3 seconds, SIGKILL */
300 just_wait, /* wait forever for the process to complete */
301 kill_only_once /* send SIGTERM and then wait */
304 typedef struct child_info child_info;
305 API_EXPORT(void) ap_note_subprocess(pool *a, int pid,
306 enum kill_conditions how);
307 API_EXPORT(int) ap_spawn_child(pool *, int (*)(void *, child_info *),
308 void *, enum kill_conditions,
309 FILE **pipe_in, FILE **pipe_out,
312 /* magic numbers --- min free bytes to consider a free pool block useable,
313 * and the min amount to allocate if we have to go to malloc() */
315 #ifndef BLOCK_MINFREE
316 #define BLOCK_MINFREE 4096
318 #ifndef BLOCK_MINALLOC
319 #define BLOCK_MINALLOC 8192
322 /* Finally, some accounting */
324 API_EXPORT(long) ap_bytes_in_pool(pool *p);
325 API_EXPORT(long) ap_bytes_in_free_blocks(void);
331 #endif /* !APACHE_ALLOC_H */