1.准备

  下载postgresql安装文件，从http://www.postgresql.org/download/下载需要的版本

安装readline（非必须）。

如果需要使用zlib，ssl等则需要先安装zlib，ssl库，不需要使用则可以不安装。

2. 创建用户

groupadd postgres

useradd -g postgres postgres

3.安装

安装什么特别的，就是三板斧 configure，make，make install

我要把pg安装在/data/pg_debug目录下。

       ./configure --prefix=/data/pg_debug/ CFLAGS="-O0" --without-readline --without-zlib

        关于参数可以使用./configure -h查看说明，这里不一一解释。说明下使用的参数含义：

        --prefix=/data/pg_debug/  是将pg安装在/data/pg_debug/ 目录下，如果不指定这个参数的话默认安装在/usr/local/pgsql目录下面

  CFLAGS="-O0" 是指gcc编译时不使用优化

--without-readline --without-zlib 不使用readline和zlib库（建议大家安装readline库，这样在命令psql命令行下可以自动不齐，我没有找到对应的版本所以没有安装）。

make

make install

安装就算完成。接下来初始化DB并启动pg：

localhost:/data/pg_debug # ls
bin  include  lib  share

localhost:/data/pg_debug # mkdir data
localhost:/data/pg_debug # chown postgres.postgres ./data
localhost:/data/pg_debug # su postgres
postgres@localhost:/data/pg_debug> /data/pg_debug/bin/initdb -D /data/pg_debug/data/

postgres@localhost:/data/pg_debug> /data/pg_debug/bin/pg_ctl start -D /data/pg_debug/data/
server starting

4。调试源码:

调试使用gdb，我使用的vi+gdb。

使用psql登录pg，并查询进程号：

postgres@localhost:/data/pg_debug> /data/pg_debug/bin/psql
psql (9.1rc1)
Type "help" for help.

postgres=# select pg_backend_pid();
 pg_backend_pid 
----------------
          21099
(1 row)

在另一终端里面使用gdb调试，并在be-secure.c的第305行设置断点：

localhost:/home/vince # gdb /data/pg_debug/bin/postgres 21099
GNU gdb (GDB) SUSE (7.2-3.3)
Copyright (C) 2010 Free Software Foundation, Inc.
License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>
This is free software: you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law.  Type "show copying"
and "show warranty" for details.
This GDB was configured as "i586-suse-linux".
For bug reporting instructions, please see:
<http://www.gnu.org/software/gdb/bugs/>...
Reading symbols from /data/pg_debug/bin/postgres...done.
Attaching to program: /data/pg_debug/bin/postgres, process 21509
Reading symbols from /lib/libdl.so.2...Missing separate debuginfo for /lib/libdl.so.2
Try: zypper install -C "debuginfo(build-id)=785eb60d6a7a2b4828cd93c6738f00065322f20d"
(no debugging symbols found)...done.
Loaded symbols for /lib/libdl.so.2
Reading symbols from /lib/libm.so.6...Missing separate debuginfo for /lib/libm.so.6
Try: zypper install -C "debuginfo(build-id)=f8e95f6424bafd41f505d4a5b113c5100ffa03be"
(no debugging symbols found)...done.
Loaded symbols for /lib/libm.so.6
Reading symbols from /lib/libc.so.6...Missing separate debuginfo for /lib/libc.so.6
Try: zypper install -C "debuginfo(build-id)=6478c346f66a284b77eb5ca82ab8f2f4f9561600"
(no debugging symbols found)...done.
Loaded symbols for /lib/libc.so.6
Reading symbols from /lib/ld-linux.so.2...Missing separate debuginfo for /lib/ld-linux.so.2
Try: zypper install -C "debuginfo(build-id)=b6b00f5560b849cf9fac5e6efb9f403c21f508dd"
(no debugging symbols found)...done.
Loaded symbols for /lib/ld-linux.so.2
0xffffe430 in __kernel_vsyscall ()

(gdb) b  be-secure.c:305

在psql中：

postgres=# create table test3(a int);

在gdb中：

(gdb) b  be-secure.c:305
Breakpoint 1 at 0x81ddb81: file be-secure.c, line 305.
(gdb) c
Continuing.

Breakpoint 1, secure_read (port=0x851f680, ptr=0x84c9280, len=8192) at be-secure.c:305
305			client_read_ended();
(gdb) n
309	}
(gdb) n
pq_recvbuf () at pqcomm.c:819
819			if (r < 0)
(gdb) 

要调试其他代码也采用同样的方法了。