view src/os/unix/ngx_errno.h @ 9300:5be23505292b

SSI: fixed incorrect or duplicate stub output. Following 3518:eb3aaf8bd2a9 (0.8.37), r->request_output is only set if there are data in the first buffer sent in the subrequest. As a result, following the change mentioned this flag cannot be used to prevent duplicate ngx_http_ssi_stub_output() calls, since it is not set if there was already some output, but the first buffer was empty. Still, when there are multiple subrequests, even an empty subrequest response might be delayed by the postpone filter, leading to a second call of ngx_http_ssi_stub_output() during finalization from ngx_http_writer() the subreqest buffers are released by the postpone filter. Since r->request_output is not set after the first call, this resulted in duplicate stub output. Additionally, checking only the first buffer might be wrong in some unusual cases. For example, the first buffer might be empty if $r->flush() is called before printing any data in the embedded Perl module. Depending on the postpone_output value and corresponding sizes, this issue can result in either duplicate or unexpected stub output, or "zero size buf in writer" alerts. Following 8124:f5515e727656 (1.23.4), it became slightly easier to reproduce the issue, as empty static files and empty cache items now result in a response with an empty buffer. Before the change, an empty proxied response can be used to reproduce the issue. Fix is check all buffers and set r->request_output if any non-empty buffers are sent. This ensures that all unusual cases of non-empty responses are covered, and also that r->request_output will be set after the first stub output, preventing duplicate output. Reported by Jan Gassen.
author Maxim Dounin <mdounin@mdounin.ru>
date Thu, 04 Jul 2024 17:41:28 +0300
parents 37ef53ecd6b0
children
line wrap: on
line source


/*
 * Copyright (C) Igor Sysoev
 * Copyright (C) Nginx, Inc.
 */


#ifndef _NGX_ERRNO_H_INCLUDED_
#define _NGX_ERRNO_H_INCLUDED_


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


typedef int               ngx_err_t;

#define NGX_EPERM         EPERM
#define NGX_ENOENT        ENOENT
#define NGX_ENOPATH       ENOENT
#define NGX_ESRCH         ESRCH
#define NGX_EINTR         EINTR
#define NGX_ECHILD        ECHILD
#define NGX_ENOMEM        ENOMEM
#define NGX_EACCES        EACCES
#define NGX_EBUSY         EBUSY
#define NGX_EEXIST        EEXIST
#define NGX_EEXIST_FILE   EEXIST
#define NGX_EXDEV         EXDEV
#define NGX_ENOTDIR       ENOTDIR
#define NGX_EISDIR        EISDIR
#define NGX_EINVAL        EINVAL
#define NGX_ENFILE        ENFILE
#define NGX_EMFILE        EMFILE
#define NGX_ENOSPC        ENOSPC
#define NGX_EPIPE         EPIPE
#define NGX_EINPROGRESS   EINPROGRESS
#define NGX_ENOPROTOOPT   ENOPROTOOPT
#define NGX_EOPNOTSUPP    EOPNOTSUPP
#define NGX_EADDRINUSE    EADDRINUSE
#define NGX_ECONNABORTED  ECONNABORTED
#define NGX_ECONNRESET    ECONNRESET
#define NGX_ENOTCONN      ENOTCONN
#define NGX_ETIMEDOUT     ETIMEDOUT
#define NGX_ECONNREFUSED  ECONNREFUSED
#define NGX_ENAMETOOLONG  ENAMETOOLONG
#define NGX_ENETDOWN      ENETDOWN
#define NGX_ENETUNREACH   ENETUNREACH
#define NGX_EHOSTDOWN     EHOSTDOWN
#define NGX_EHOSTUNREACH  EHOSTUNREACH
#define NGX_ENOSYS        ENOSYS
#define NGX_ECANCELED     ECANCELED
#define NGX_EILSEQ        EILSEQ
#define NGX_ENOMOREFILES  0
#define NGX_ELOOP         ELOOP
#define NGX_EBADF         EBADF
#define NGX_EMSGSIZE      EMSGSIZE
#define NGX_ENOBUFS       ENOBUFS

#if (NGX_HAVE_OPENAT)
#define NGX_EMLINK        EMLINK
#endif

#if (__hpux__)
#define NGX_EAGAIN        EWOULDBLOCK
#else
#define NGX_EAGAIN        EAGAIN
#endif


#define ngx_errno                  errno
#define ngx_socket_errno           errno
#define ngx_set_errno(err)         errno = err
#define ngx_set_socket_errno(err)  errno = err


u_char *ngx_strerror(ngx_err_t err, u_char *errstr, size_t size);
ngx_int_t ngx_strerror_init(void);


#endif /* _NGX_ERRNO_H_INCLUDED_ */