pcre2/doc/pcre2_jit_stack_assign.3

.TH PCRE2_JIT_STACK_ASSIGN 3 "28 June 2018" "PCRE2 10.32"
.SH NAME
PCRE2 - Perl-compatible regular expressions (revised API)
.SH SYNOPSIS
.rs
.sp
.B #include <pcre2.h>
.PP
.nf
.B void pcre2_jit_stack_assign(pcre2_match_context *\fImcontext\fP,
.B "  pcre2_jit_callback \fIcallback_function\fP, void *\fIcallback_data\fP);"
.fi
.
.SH DESCRIPTION
.rs
.sp
This function provides control over the memory used by JIT as a run-time stack
when \fBpcre2_match()\fP or \fBpcre2_jit_match()\fP is called with a pattern
that has been successfully processed by the JIT compiler. The information that
determines which stack is used is put into a match context that is subsequently
passed to a matching function. The arguments of this function are:
.sp
  mcontext       a pointer to a match context
  callback       a callback function
  callback_data  a JIT stack or a value to be passed to the callback
.P
If \fImcontext\fP is NULL, the function returns immediately, without doing 
anything.   
.P
If \fIcallback\fP is NULL and \fIcallback_data\fP is NULL, an internal 32KiB
block on the machine stack is used.
.P
If \fIcallback\fP is NULL and \fIcallback_data\fP is not NULL,
\fIcallback_data\fP must be a valid JIT stack, the result of calling
\fBpcre2_jit_stack_create()\fP.
.P
If \fIcallback\fP not NULL, it is called with \fIcallback_data\fP as an
argument at the start of matching, in order to set up a JIT stack. If the
result is NULL, the internal 32KiB stack is used; otherwise the return value
must be a valid JIT stack, the result of calling
\fBpcre2_jit_stack_create()\fP.
.P
You may safely use the same JIT stack for multiple patterns, as long as they
are all matched in the same thread. In a multithread application, each thread
must use its own JIT stack. For more details, see the
.\" HREF
\fBpcre2jit\fP
.\"
page.
.P
There is a complete description of the PCRE2 native API in the
.\" HREF
\fBpcre2api\fP
.\"
page and a description of the POSIX API in the
.\" HREF
\fBpcre2posix\fP
.\"
page.