view src/core/ngx_conf_file.h @ 8018:5119c8150478

Fixed runtime handling of systems without EPOLLRDHUP support. In 7583:efd71d49bde0 (nginx 1.17.5) along with introduction of the ioctl(FIONREAD) support proper handling of systems without EPOLLRDHUP support in the kernel (but with EPOLLRDHUP in headers) was broken. Before the change, rev->available was never set to 0 unless ngx_use_epoll_rdhup was also set (that is, runtime test for EPOLLRDHUP introduced in 6536:f7849bfb6d21 succeeded). After the change, rev->available might reach 0 on systems without runtime EPOLLRDHUP support, stopping further reading in ngx_readv_chain() and ngx_unix_recv(). And, if EOF happened to be already reported along with the last event, it is not reported again by epoll_wait(), leading to connection hangs and timeouts on such systems. This affects Linux kernels before 2.6.17 if nginx was compiled with newer headers, and, more importantly, emulation layers, such as DigitalOcean's App Platform's / gVisor's epoll emulation layer. Fix is to explicitly check ngx_use_epoll_rdhup before the corresponding rev->pending_eof tests in ngx_readv_chain() and ngx_unix_recv().
author Marcus Ball <marcus.ball@live.com>
date Mon, 30 May 2022 02:38:07 +0300
parents b7a7c02aea3a
children
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/*
 * Copyright (C) Igor Sysoev
 * Copyright (C) Nginx, Inc.
 */


#ifndef _NGX_CONF_FILE_H_INCLUDED_
#define _NGX_CONF_FILE_H_INCLUDED_


#include <ngx_config.h>
#include <ngx_core.h>


/*
 *        AAAA  number of arguments
 *      FF      command flags
 *    TT        command type, i.e. HTTP "location" or "server" command
 */

#define NGX_CONF_NOARGS      0x00000001
#define NGX_CONF_TAKE1       0x00000002
#define NGX_CONF_TAKE2       0x00000004
#define NGX_CONF_TAKE3       0x00000008
#define NGX_CONF_TAKE4       0x00000010
#define NGX_CONF_TAKE5       0x00000020
#define NGX_CONF_TAKE6       0x00000040
#define NGX_CONF_TAKE7       0x00000080

#define NGX_CONF_MAX_ARGS    8

#define NGX_CONF_TAKE12      (NGX_CONF_TAKE1|NGX_CONF_TAKE2)
#define NGX_CONF_TAKE13      (NGX_CONF_TAKE1|NGX_CONF_TAKE3)

#define NGX_CONF_TAKE23      (NGX_CONF_TAKE2|NGX_CONF_TAKE3)

#define NGX_CONF_TAKE123     (NGX_CONF_TAKE1|NGX_CONF_TAKE2|NGX_CONF_TAKE3)
#define NGX_CONF_TAKE1234    (NGX_CONF_TAKE1|NGX_CONF_TAKE2|NGX_CONF_TAKE3   \
                              |NGX_CONF_TAKE4)

#define NGX_CONF_ARGS_NUMBER 0x000000ff
#define NGX_CONF_BLOCK       0x00000100
#define NGX_CONF_FLAG        0x00000200
#define NGX_CONF_ANY         0x00000400
#define NGX_CONF_1MORE       0x00000800
#define NGX_CONF_2MORE       0x00001000

#define NGX_DIRECT_CONF      0x00010000

#define NGX_MAIN_CONF        0x01000000
#define NGX_ANY_CONF         0xFF000000



#define NGX_CONF_UNSET       -1
#define NGX_CONF_UNSET_UINT  (ngx_uint_t) -1
#define NGX_CONF_UNSET_PTR   (void *) -1
#define NGX_CONF_UNSET_SIZE  (size_t) -1
#define NGX_CONF_UNSET_MSEC  (ngx_msec_t) -1


#define NGX_CONF_OK          NULL
#define NGX_CONF_ERROR       (void *) -1

#define NGX_CONF_BLOCK_START 1
#define NGX_CONF_BLOCK_DONE  2
#define NGX_CONF_FILE_DONE   3

#define NGX_CORE_MODULE      0x45524F43  /* "CORE" */
#define NGX_CONF_MODULE      0x464E4F43  /* "CONF" */


#define NGX_MAX_CONF_ERRSTR  1024


struct ngx_command_s {
    ngx_str_t             name;
    ngx_uint_t            type;
    char               *(*set)(ngx_conf_t *cf, ngx_command_t *cmd, void *conf);
    ngx_uint_t            conf;
    ngx_uint_t            offset;
    void                 *post;
};

#define ngx_null_command  { ngx_null_string, 0, NULL, 0, 0, NULL }


struct ngx_open_file_s {
    ngx_fd_t              fd;
    ngx_str_t             name;

    void                (*flush)(ngx_open_file_t *file, ngx_log_t *log);
    void                 *data;
};


typedef struct {
    ngx_file_t            file;
    ngx_buf_t            *buffer;
    ngx_buf_t            *dump;
    ngx_uint_t            line;
} ngx_conf_file_t;


typedef struct {
    ngx_str_t             name;
    ngx_buf_t            *buffer;
} ngx_conf_dump_t;


typedef char *(*ngx_conf_handler_pt)(ngx_conf_t *cf,
    ngx_command_t *dummy, void *conf);


struct ngx_conf_s {
    char                 *name;
    ngx_array_t          *args;

    ngx_cycle_t          *cycle;
    ngx_pool_t           *pool;
    ngx_pool_t           *temp_pool;
    ngx_conf_file_t      *conf_file;
    ngx_log_t            *log;

    void                 *ctx;
    ngx_uint_t            module_type;
    ngx_uint_t            cmd_type;

    ngx_conf_handler_pt   handler;
    void                 *handler_conf;
};


typedef char *(*ngx_conf_post_handler_pt) (ngx_conf_t *cf,
    void *data, void *conf);

typedef struct {
    ngx_conf_post_handler_pt  post_handler;
} ngx_conf_post_t;


typedef struct {
    ngx_conf_post_handler_pt  post_handler;
    char                     *old_name;
    char                     *new_name;
} ngx_conf_deprecated_t;


typedef struct {
    ngx_conf_post_handler_pt  post_handler;
    ngx_int_t                 low;
    ngx_int_t                 high;
} ngx_conf_num_bounds_t;


typedef struct {
    ngx_str_t                 name;
    ngx_uint_t                value;
} ngx_conf_enum_t;


#define NGX_CONF_BITMASK_SET  1

typedef struct {
    ngx_str_t                 name;
    ngx_uint_t                mask;
} ngx_conf_bitmask_t;



char * ngx_conf_deprecated(ngx_conf_t *cf, void *post, void *data);
char *ngx_conf_check_num_bounds(ngx_conf_t *cf, void *post, void *data);


#define ngx_get_conf(conf_ctx, module)  conf_ctx[module.index]



#define ngx_conf_init_value(conf, default)                                   \
    if (conf == NGX_CONF_UNSET) {                                            \
        conf = default;                                                      \
    }

#define ngx_conf_init_ptr_value(conf, default)                               \
    if (conf == NGX_CONF_UNSET_PTR) {                                        \
        conf = default;                                                      \
    }

#define ngx_conf_init_uint_value(conf, default)                              \
    if (conf == NGX_CONF_UNSET_UINT) {                                       \
        conf = default;                                                      \
    }

#define ngx_conf_init_size_value(conf, default)                              \
    if (conf == NGX_CONF_UNSET_SIZE) {                                       \
        conf = default;                                                      \
    }

#define ngx_conf_init_msec_value(conf, default)                              \
    if (conf == NGX_CONF_UNSET_MSEC) {                                       \
        conf = default;                                                      \
    }

#define ngx_conf_merge_value(conf, prev, default)                            \
    if (conf == NGX_CONF_UNSET) {                                            \
        conf = (prev == NGX_CONF_UNSET) ? default : prev;                    \
    }

#define ngx_conf_merge_ptr_value(conf, prev, default)                        \
    if (conf == NGX_CONF_UNSET_PTR) {                                        \
        conf = (prev == NGX_CONF_UNSET_PTR) ? default : prev;                \
    }

#define ngx_conf_merge_uint_value(conf, prev, default)                       \
    if (conf == NGX_CONF_UNSET_UINT) {                                       \
        conf = (prev == NGX_CONF_UNSET_UINT) ? default : prev;               \
    }

#define ngx_conf_merge_msec_value(conf, prev, default)                       \
    if (conf == NGX_CONF_UNSET_MSEC) {                                       \
        conf = (prev == NGX_CONF_UNSET_MSEC) ? default : prev;               \
    }

#define ngx_conf_merge_sec_value(conf, prev, default)                        \
    if (conf == NGX_CONF_UNSET) {                                            \
        conf = (prev == NGX_CONF_UNSET) ? default : prev;                    \
    }

#define ngx_conf_merge_size_value(conf, prev, default)                       \
    if (conf == NGX_CONF_UNSET_SIZE) {                                       \
        conf = (prev == NGX_CONF_UNSET_SIZE) ? default : prev;               \
    }

#define ngx_conf_merge_off_value(conf, prev, default)                        \
    if (conf == NGX_CONF_UNSET) {                                            \
        conf = (prev == NGX_CONF_UNSET) ? default : prev;                    \
    }

#define ngx_conf_merge_str_value(conf, prev, default)                        \
    if (conf.data == NULL) {                                                 \
        if (prev.data) {                                                     \
            conf.len = prev.len;                                             \
            conf.data = prev.data;                                           \
        } else {                                                             \
            conf.len = sizeof(default) - 1;                                  \
            conf.data = (u_char *) default;                                  \
        }                                                                    \
    }

#define ngx_conf_merge_bufs_value(conf, prev, default_num, default_size)     \
    if (conf.num == 0) {                                                     \
        if (prev.num) {                                                      \
            conf.num = prev.num;                                             \
            conf.size = prev.size;                                           \
        } else {                                                             \
            conf.num = default_num;                                          \
            conf.size = default_size;                                        \
        }                                                                    \
    }

#define ngx_conf_merge_bitmask_value(conf, prev, default)                    \
    if (conf == 0) {                                                         \
        conf = (prev == 0) ? default : prev;                                 \
    }


char *ngx_conf_param(ngx_conf_t *cf);
char *ngx_conf_parse(ngx_conf_t *cf, ngx_str_t *filename);
char *ngx_conf_include(ngx_conf_t *cf, ngx_command_t *cmd, void *conf);


ngx_int_t ngx_conf_full_name(ngx_cycle_t *cycle, ngx_str_t *name,
    ngx_uint_t conf_prefix);
ngx_open_file_t *ngx_conf_open_file(ngx_cycle_t *cycle, ngx_str_t *name);
void ngx_cdecl ngx_conf_log_error(ngx_uint_t level, ngx_conf_t *cf,
    ngx_err_t err, const char *fmt, ...);


char *ngx_conf_set_flag_slot(ngx_conf_t *cf, ngx_command_t *cmd, void *conf);
char *ngx_conf_set_str_slot(ngx_conf_t *cf, ngx_command_t *cmd, void *conf);
char *ngx_conf_set_str_array_slot(ngx_conf_t *cf, ngx_command_t *cmd,
    void *conf);
char *ngx_conf_set_keyval_slot(ngx_conf_t *cf, ngx_command_t *cmd, void *conf);
char *ngx_conf_set_num_slot(ngx_conf_t *cf, ngx_command_t *cmd, void *conf);
char *ngx_conf_set_size_slot(ngx_conf_t *cf, ngx_command_t *cmd, void *conf);
char *ngx_conf_set_off_slot(ngx_conf_t *cf, ngx_command_t *cmd, void *conf);
char *ngx_conf_set_msec_slot(ngx_conf_t *cf, ngx_command_t *cmd, void *conf);
char *ngx_conf_set_sec_slot(ngx_conf_t *cf, ngx_command_t *cmd, void *conf);
char *ngx_conf_set_bufs_slot(ngx_conf_t *cf, ngx_command_t *cmd, void *conf);
char *ngx_conf_set_enum_slot(ngx_conf_t *cf, ngx_command_t *cmd, void *conf);
char *ngx_conf_set_bitmask_slot(ngx_conf_t *cf, ngx_command_t *cmd, void *conf);


#endif /* _NGX_CONF_FILE_H_INCLUDED_ */