/* ==================================================================== * Copyright (c) 1995 The Apache Group. All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in * the documentation and/or other materials provided with the * distribution. * * 3. All advertising materials mentioning features or use of this * software must display the following acknowledgment: * "This product includes software developed by the Apache Group * for use in the Apache HTTP server project (http://www.apache.org/)." * * 4. The names "Apache Server" and "Apache Group" must not be used to * endorse or promote products derived from this software without * prior written permission. * * 5. Redistributions of any form whatsoever must retain the following * acknowledgment: * "This product includes software developed by the Apache Group * for use in the Apache HTTP server project (http://www.apache.org/)." * * THIS SOFTWARE IS PROVIDED BY THE APACHE GROUP ``AS IS'' AND ANY * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE APACHE GROUP OR * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED * OF THE POSSIBILITY OF SUCH DAMAGE. * ==================================================================== * * This software consists of voluntary contributions made by many * individuals on behalf of the Apache Group and was originally based * on public domain software written at the National Center for * Supercomputing Applications, University of Illinois, Urbana-Champaign. * For more information on the Apache Group and the Apache HTTP server * project, please see . * */ /* * Resource allocation routines... * * designed so that we don't have to keep track of EVERYTHING so that * it can be explicitly freed later (a fundamentally unsound strategy --- * particularly in the presence of die()). * * Instead, we maintain pools, and allocate items (both memory and I/O * handlers) from the pools --- currently there are two, one for per * transaction info, and one for config info. When a transaction is over, * we can delete everything in the per-transaction pool without fear, and * without thinking too hard about it either. * * rst */ /* Arenas for configuration info and transaction info * --- actual layout of the pool structure is private to * alloc.c. */ typedef struct pool pool; extern pool *permanent_pool; void init_alloc(); /* Set up everything */ pool *make_sub_pool (pool *); /* All pools are subpools of permanent_pool */ void destroy_pool (pool *); /* Clearing out EVERYTHING in an pool... destroys any sub-pools */ void clear_pool (struct pool *); /* Preparing for exec() --- close files, etc., but *don't* flush I/O * buffers, *don't* wait for subprocesses, and *don't* free any memory. */ void cleanup_for_exec (); /* routines to allocate memory from an pool... */ void *palloc(struct pool *, int nbytes); void *pcalloc(struct pool *, int nbytes); extern char *pstrdup(struct pool *, const char *s); char *pstrcat(struct pool *, ...); /* all '...' must be char* */ /* array and alist management... keeping lists of things. * Common enough to want common support code ... */ typedef struct { pool *pool; int elt_size; int nelts; int nalloc; char *elts; } array_header; array_header *make_array (pool *p, int nelts, int elt_size); void *push_array (array_header *); void array_cat (array_header *dst, array_header *src); array_header *append_arrays (pool *, array_header *, array_header *); /* copy_array copies the *entire* array. copy_array_hdr just copies * the header, and arranges for the elements to be copied if (and only * if) the code subsequently does a push or arraycat. */ array_header *copy_array (pool *p, array_header *src); array_header *copy_array_hdr (pool *p, array_header *src); /* Tables. Implemented alist style, for now, though we try to keep * it so that imposing a hash table structure on top in the future * wouldn't be *too* hard... * * Note that key comparisons for these are case-insensitive, largely * because that's what's appropriate and convenient everywhere they're * currently being used... */ typedef array_header table; typedef struct { char *key; /* maybe NULL in future; * check when iterating thru table_elts */ char *val; } table_entry; table *make_table (pool *p, int nelts); table *copy_table (pool *p, table *); char *table_get (table *, char *); void table_set (table *, char *name, char *val); void table_merge (table *, char *name, char *more_val); table *overlay_tables (pool *p, table *overlay, table *base); array_header *table_elts (table *); /* routines to remember allocation of other sorts of things... * generic interface first. Note that we want to have two separate * cleanup functions in the general case, one for exec() preparation, * to keep CGI scripts and the like from inheriting access to things * they shouldn't be able to touch, and one for actually cleaning up, * when the actual server process wants to get rid of the thing, * whatever it is. * * kill_cleanup disarms a cleanup, presumably because the resource in * question has been closed, freed, or whatever, and it's scarce * enough to want to reclaim (e.g., descriptors). It arranges for the * resource not to be cleaned up a second time (it might have been * reallocated). run_cleanup does the same, but runs it first. * * Cleanups are identified for purposes of finding & running them off by the * plain_cleanup and data, which should presumably be unique. * * NB any code which invokes register_cleanup or kill_cleanup directly * is a critical section which should be guarded by block_alarms() and * unblock_alarms() below... */ void register_cleanup (pool *p, void *data, void (*plain_cleanup)(void *), void (*child_cleanup)(void *)); void kill_cleanup (pool *p, void *data, void (*plain_cleanup)(void *)); /* The time between when a resource is actually allocated, and when it * its cleanup is registered is a critical section, during which the * resource could leak if we got interrupted or timed out. So, anything * which registers cleanups should bracket resource allocation and the * cleanup registry with these. (This is done internally by run_cleanup). * * NB they are actually implemented in http_main.c, since they are bound * up with timeout handling in general... */ extern void block_alarms(); extern void unblock_alarms(); /* Common cases which want utility support.. * the note_cleanups_for_foo routines are for */ FILE *pfopen(struct pool *, char *name, char *fmode); FILE *pfdopen(struct pool *, int fd, char *fmode); int popenf(struct pool *, char *name, int flg, int mode); void note_cleanups_for_file (pool *, FILE *); void note_cleanups_for_fd (pool *, int); /* routines to note closes... file descriptors are constrained enough * on some systems that we want to support this. */ int pfclose(struct pool *, FILE *); int pclosef(struct pool *, int fd); /* ... even child processes (which we may want to wait for, * or to kill outright, on unexpected termination). * * spawn_child is a utility routine which handles an awful lot of * the rigamarole associated with spawning a child --- it arranges * for pipes to the child's stdin and stdout, if desired (if not, * set the associated args to NULL). It takes as args a function * to call in the child, and an argument to be passed to the function. */ enum kill_conditions { kill_never, kill_always, kill_after_timeout, just_wait}; int spawn_child (pool *, void (*)(void *), void *, enum kill_conditions, FILE **pipe_in, FILE **pipe_out); #ifdef __EMX__ int spawn_child_os2 (pool *, void (*)(void *), void *, enum kill_conditions, FILE **pipe_in, FILE **pipe_out, char *buffer, int lenp); #endif /* magic numbers --- only one so far, min free bytes in a new pool block */ #define BLOCK_MINFREE 8192 /* Finally, some accounting */ long bytes_in_pool(pool *p); long bytes_in_free_blocks();