How to integrate snappy into xhprof in php

Object introduction
xhprof: PHP performance analysis tool, a PHP extension developed by Facebook, which can record the function/class method call chain during the running of PHP scripts, as well as the time consumed by each call, memory usage and other data;
snappy: A string compression/decompression tool developed by Google. The advantage is fast compression speed.

Goal
Provide two PHP functions xhprof_compress($str) and xhprof_uncompress($str) in the xhprof extension to implement compression and decompression functions.

Specific process
1. Download the xhprof source code to php-5.6.24/ext/xhprof
2. Follow the normal way./configure, make, make sure xhprof.so is working properly
3. Download the snappy source code to php-5.6.24 /ext/xhprof/snappy
4. Edit the file php-5.6.24/ext/xhprof/php_xhprof.h and add the following lines:

...
PHP_FUNCTION(xhprof_compress);
PHP_FUNCTION(xhprof_uncompress);
...

5. Edit the file php-5.6.24/ext/xhprof/xhprof.c and add the following line:

 ...
 #include "snappy/snappy-c.h"
 ...

 zend_function_entry xhprof_functions[] = {
   ...
   PHP_FE(xhprof_compress, NULL)
   PHP_FE(xhprof_uncompress, NULL)
   ...
 };

 PHP_FUNCTION(xhprof_compress)
 {
     zval *data;
     char *output;
     size_t output_len;

     if (zend_parse_parameters(ZEND_NUM_ARGS() TSRMLS_CC,
                               "z", &data) == FAILURE) {
         RETURN_FALSE;
     }

     if (Z_TYPE_P(data) != IS_STRING) {
         zend_error(E_WARNING,
                    "snappy_compress : expects parameter to be string.");
         RETURN_FALSE;
     }

     output_len = snappy_max_compressed_length(Z_STRLEN_P(data));
     output = (char *)emalloc(output_len);
     if (!output) {
         zend_error(E_WARNING, "snappy_compress : memory error");
         RETURN_FALSE;
     }


     if (snappy_compress(Z_STRVAL_P(data), Z_STRLEN_P(data),
                         output, &output_len) == SNAPPY_OK) {
 #if ZEND_MODULE_API_NO >= 20141001
         RETVAL_STRINGL(output, output_len);
 #else
         RETVAL_STRINGL(output, output_len, 1);
 #endif
     } else {
         RETVAL_FALSE;
     }
    efree(output);
 }
 PHP_FUNCTION(xhprof_uncompress)
 {
     zval *data;
     char *output = NULL;
     size_t output_len;

     if (zend_parse_parameters(ZEND_NUM_ARGS() TSRMLS_CC,
                               "z", &data) == FAILURE) {
         RETURN_FALSE;
     }

     if (Z_TYPE_P(data) != IS_STRING) {
         zend_error(E_WARNING,
                    "snappy_uncompress : expects parameter to be string.");
         RETURN_FALSE;
     }

     if (snappy_uncompressed_length(Z_STRVAL_P(data), Z_STRLEN_P(data),
                                    &output_len) != SNAPPY_OK) {
         zend_error(E_WARNING, "snappy_uncompress : output length error");
         RETURN_FALSE;
     }

     output = (char *)emalloc(output_len);
     if (!output) {
         zend_error(E_WARNING, "snappy_uncompress : memory error");
         RETURN_FALSE;
     }

     if (snappy_uncompress(Z_STRVAL_P(data), Z_STRLEN_P(data),
                           output, &output_len) == SNAPPY_OK) {
 #if ZEND_MODULE_API_NO >= 20141001
         RETVAL_STRINGL(output, output_len);
 #else
         RETVAL_STRINGL(output, output_len, 1);
 #endif
     } else {
         zend_error(E_WARNING, "snappy_uncompress : data error");
         RETVAL_FALSE;
     }

     efree(output);
 }
...

The above code is not original and is taken from snappy’s PHP extension: php-ext-snappy
6. Edit config. The m4 file specifies the compilation method of snappy. The complete config.m4 code is as follows. Snappy will be edited directly into xhprof.so. A better way would be to first check whether snappy is installed on the current host. If so, specify the link library path, so there is no need to compile snappy related functions into xhprof.so.

PHP_ARG_ENABLE(xhprof, whether to enable xhprof support,
 [ --enable-xhprof      Enable xhprof support])

 dnl compiler C++:
 PHP_REQUIRE_CXX()

 dnl snappy
 SNAPPY_MAJOR="1"
 SNAPPY_MINOR="1"
 SNAPPY_PATCHLEVEL="3"

 AC_PROG_CXX
 AC_LANG([C++])
 AC_C_BIGENDIAN
 AC_CHECK_HEADERS([stdint.h stddef.h sys/mman.h sys/resource.h windows.h byteswap.h sys/byteswap.  h sys/endian.h sys/time.h])

 AC_CHECK_FUNC([mmap])

 AC_MSG_CHECKING([if the compiler supports __builtin_expect])
 AC_TRY_COMPILE(, [
 return __builtin_expect(1, 1) ? 1 : 0
 ], [
 snappy_have_builtin_expect=yes
 AC_MSG_RESULT([yes])
 ], [
 snappy_have_builtin_expect=no
 AC_MSG_RESULT([no])
 ])
 if test x$snappy_have_builtin_expect = xyes ; then
 AC_DEFINE([HAVE_BUILTIN_EXPECT], [1], [Define to 1 if the compiler supports __builtin_expect.])
 fi

 AC_MSG_CHECKING([if the compiler supports __builtin_ctzll])
 AC_TRY_COMPILE(, [
 return (__builtin_ctzll(0x100000000LL) == 32) ? 1 : 0
 ], [
 snappy_have_builtin_ctz=yes
 AC_MSG_RESULT([yes])
 ], [
 snappy_have_builtin_ctz=no
 AC_MSG_RESULT([no])
 ])
 if test x$snappy_have_builtin_ctz = xyes ; then
 AC_DEFINE([HAVE_BUILTIN_CTZ], [1], [Define to 1 if the compiler supports __builtin_ctz and        friends.])
 fi

 if test "$ac_cv_header_stdint_h" = "yes"; then
 AC_SUBST([ac_cv_have_stdint_h], [1])
 else
 AC_SUBST([ac_cv_have_stdint_h], [0])
 fi
 if test "$ac_cv_header_stddef_h" = "yes"; then
 AC_SUBST([ac_cv_have_stddef_h], [1])
 else
 AC_SUBST([ac_cv_have_stddef_h], [0])
 fi
 if test "$ac_cv_header_sys_uio_h" = "yes"; then
 AC_SUBST([ac_cv_have_sys_uio_h], [1])
 else
 AC_SUBST([ac_cv_have_sys_uio_h], [0])
 fi

 AC_SUBST([SNAPPY_MAJOR])
 AC_SUBST([SNAPPY_MINOR])
 AC_SUBST([SNAPPY_PATCHLEVEL])

 AC_CONFIG_FILES([snappy/snappy-stubs-public.h])
 AC_OUTPUT
dnl Check for stdc++
 LIBNAME=stdc++
 AC_MSG_CHECKING([for stdc++])
 AC_LANG_SAVE
 AC_LANG_CPLUSPLUS
 AC_TRY_COMPILE(
 [
 #include <string>
 using namespace std;
 ],[
 string dummy;
 ],[
 AC_MSG_RESULT(yes)
 PHP_ADD_LIBRARY($LIBNAME, , XHPROF_SHARED_LIBADD)
 ],[
 AC_MSG_ERROR([wrong stdc++ library not found])
 ])
 AC_LANG_RESTORE

 PHP_SUBST(XHPROF_SHARED_LIBADD)

 dnl Sources
 SNAPPY_SOURCES="snappy/snappy-c.cc snappy/snappy.cc snappy/snappy-stubs-internal.cc snappy/       snappy-sinksource.cc"
 if test "$PHP_XHPROF" != "no"; then
   PHP_NEW_EXTENSION(xhprof, xhprof.c $SNAPPY_SOURCES, $ext_shared)
 fi

The above code is not original and is taken from snappy’s PHP extension: php-ext-snappy

7. After re-executing phpize, execute make to generate a new xhprof.so
8. Execute the command nm xhprof.so to view snappy related information Whether the function has been compiled successfully, as shown below, the memory addresses of _snappy_compress, _snappy_uncompress, etc. are all non-empty, indicating that they have been compiled into xhprof.so.

➜  xhprof  nm modules/xhprof.so
0000000000008a98 s GCC_except_table10
0000000000008ad8 s GCC_except_table11
0000000000008b24 s GCC_except_table12
0000000000008b70 s GCC_except_table13
0000000000008bb0 s GCC_except_table14
0000000000008bfc s GCC_except_table16
0000000000008c48 s GCC_except_table18
0000000000008cbc s GCC_except_table19
0000000000008d4c s GCC_except_table23
00000000000088f4 s GCC_except_table5
0000000000008934 s GCC_except_table7
0000000000008a0c s GCC_except_table8
0000000000008a4c s GCC_except_table9
...
0000000000002510 T _restore_cpu_affinity
0000000000003f00 T _snappy_compress
0000000000003f60 T _snappy_max_compressed_length
0000000000003f70 T _snappy_uncompress
0000000000003fe0 T _snappy_uncompressed_length
0000000000004000 T _snappy_validate_compressed_buffer
...
                 U _zend_register_long_constant
                 U _zend_unregister_ini_entries
00000000000013a0 T _zif_xhprof_compress
0000000000001090 T _zif_xhprof_disable
0000000000001350 T _zif_xhprof_dump
0000000000001040 T _zif_xhprof_enable
0000000000001200 T _zif_xhprof_sample_disable
00000000000011e0 T _zif_xhprof_sample_enable
0000000000001470 T _zif_xhprof_uncompress
0000000000001700 T _zm_activate_xhprof
0000000000001720 T _zm_deactivate_xhprof
0000000000001960 T _zm_info_xhprof
0000000000001660 T _zm_shutdown_xhprof
0000000000001560 T _zm_startup_xhprof
0000000000001f00 t _zval_dump
                 U _zval_used_for_init

9. You can use xhprof_compress() and xhrof_uncompress() in php script