view src/os/win32/ngx_process.h @ 6133:af7eba90645d

Win32: shared memory base addresses and remapping. Two mechanisms are implemented to make it possible to store pointers in shared memory on Windows, in particular on Windows Vista and later versions with ASLR: - The ngx_shm_remap() function added to allow remapping of a shared memory zone to the address originally used for it in the master process. While important, it doesn't solve the problem by itself as in many cases it's not possible to use the address because of conflicts with other allocations. - We now create mappings at the same address in all processes by starting mappings at predefined addresses normally unused by newborn processes. These two mechanisms combined allow to use shared memory on Windows almost without problems, including reloads. Based on the patch by Sergey Brester: http://mailman.nginx.org/pipermail/nginx-devel/2015-April/006836.html
author Maxim Dounin <mdounin@mdounin.ru>
date Mon, 27 Apr 2015 18:25:42 +0300
parents d620f497c50f
children 7296b38f6416
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/*
 * Copyright (C) Igor Sysoev
 * Copyright (C) Nginx, Inc.
 */


#ifndef _NGX_PROCESS_H_INCLUDED_
#define _NGX_PROCESS_H_INCLUDED_


typedef DWORD               ngx_pid_t;
#define NGX_INVALID_PID     0


#define ngx_getpid          GetCurrentProcessId
#define ngx_log_pid         ngx_pid


#define NGX_PROCESS_SYNC_NAME                                                 \
    (sizeof("ngx_cache_manager_mutex_") + NGX_INT32_LEN)


typedef struct {
    HANDLE                  handle;
    ngx_pid_t               pid;
    char                   *name;

    HANDLE                  term;
    HANDLE                  quit;
    HANDLE                  reopen;

    u_char                  term_event[NGX_PROCESS_SYNC_NAME];
    u_char                  quit_event[NGX_PROCESS_SYNC_NAME];
    u_char                  reopen_event[NGX_PROCESS_SYNC_NAME];

    unsigned                just_spawn:1;
    unsigned                exiting:1;
} ngx_process_t;


typedef struct {
    char                   *path;
    char                   *name;
    char                   *args;
    char *const            *argv;
    char *const            *envp;
    HANDLE                  child;
} ngx_exec_ctx_t;


ngx_pid_t ngx_spawn_process(ngx_cycle_t *cycle, char *name, ngx_int_t respawn);
ngx_pid_t ngx_execute(ngx_cycle_t *cycle, ngx_exec_ctx_t *ctx);

#define ngx_debug_point()
#define ngx_sched_yield()   SwitchToThread()


#define NGX_MAX_PROCESSES         (MAXIMUM_WAIT_OBJECTS - 4)

#define NGX_PROCESS_RESPAWN       -2
#define NGX_PROCESS_JUST_RESPAWN  -3


extern int                  ngx_argc;
extern char               **ngx_argv;
extern char               **ngx_os_argv;

extern ngx_int_t            ngx_last_process;
extern ngx_process_t        ngx_processes[NGX_MAX_PROCESSES];

extern ngx_pid_t            ngx_pid;


#endif /* _NGX_PROCESS_H_INCLUDED_ */