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象GDB,CDB這些工具，命令都很多，但是我們只要熟記最常用的"三板斧"就可以工作了。
1.啟動
1)直接調試:
gdb program [core]
cdb program or cdb -z DumpFile
2)attach方式
gdb attach pid
cdb -pn ExeName or cdb -p pid
2.顯示堆棧
GDB: bt
CDB: k
3. 設置斷點
GDB: b [file:]line
CDB: bp 'file:line'
4. 運行/繼續運行
GDB: run [arglist]
c 繼續運行
CDB: g
5. 單步
GDB : n (step over) s (step into)
CDB : p
6. 打印變量的值
GDB : p expr
CDB: ? expr
說老實話,CDB過于復雜，學起來比GDB難.
BTW:用CDB之前設置一下symbol的path
set _NT_SYMBOL_PATH=srv*c:\symbols*http://msdl.microsoft.com/download/symbols
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<!DOCTYPE?HTML?PUBLIC?"-//W3C//DTD?HTML?4.0?Transitional//EN">
<HTML>
<HEAD>
<TITLE>?An?utf8?count?tool??</TITLE>
<meta?http-equiv="Content-Type"?content="text/html;?charset=utf16">
<script>
????function?utf16to8(str)?{
????????var?out,?i,?len,?c;
????????out?=?"";
????????len?=?str.length;
????????for(i?=?0;?i?<?len;?i++)?{
????????c?=?str.charCodeAt(i);
????????if?((c?>=?0x0001)?&&?(c?<=?0x007F))?{
????????????out?+=?str.charAt(i);
????????}?else?if?(c?>?0x07FF)?{
????????????out?+=?String.fromCharCode(0xE0?|?((c?>>?12)?&?0x0F));
????????????out?+=?String.fromCharCode(0x80?|?((c?>>??6)?&?0x3F));
????????????out?+=?String.fromCharCode(0x80?|?((c?>>??0)?&?0x3F));
????????}?else?{
????????????out?+=?String.fromCharCode(0xC0?|?((c?>>??6)?&?0x1F));
????????????out?+=?String.fromCharCode(0x80?|?((c?>>??0)?&?0x3F));
????????}
????????}
????????return?out;
????}
????function?count()
????{
????????var?temp?=?f1.value;
????????temp=temp.replace(/\\r/g,"\r");
????????temp=temp.replace(/\\n/g,"\n");
????????result.innerHTML=utf16to8(temp).length;
????}
</script>
</HEAD>
<BODY>
<TEXTAREA?id="f1"?NAME="f1"?ROWS="10"?COLS="50"></TEXTAREA>
<br/>
<INPUT?TYPE="button"?value="count?length"?onclick="count()">
<div?id="result"></div>
</BODY>
</HTML>
<HTML>
<HEAD>
<TITLE>?An?utf8?count?tool??</TITLE>
<meta?http-equiv="Content-Type"?content="text/html;?charset=utf16">
<script>
????function?utf16to8(str)?{
????????var?out,?i,?len,?c;
????????out?=?"";
????????len?=?str.length;
????????for(i?=?0;?i?<?len;?i++)?{
????????c?=?str.charCodeAt(i);
????????if?((c?>=?0x0001)?&&?(c?<=?0x007F))?{
????????????out?+=?str.charAt(i);
????????}?else?if?(c?>?0x07FF)?{
????????????out?+=?String.fromCharCode(0xE0?|?((c?>>?12)?&?0x0F));
????????????out?+=?String.fromCharCode(0x80?|?((c?>>??6)?&?0x3F));
????????????out?+=?String.fromCharCode(0x80?|?((c?>>??0)?&?0x3F));
????????}?else?{
????????????out?+=?String.fromCharCode(0xC0?|?((c?>>??6)?&?0x1F));
????????????out?+=?String.fromCharCode(0x80?|?((c?>>??0)?&?0x3F));
????????}
????????}
????????return?out;
????}
????function?count()
????{
????????var?temp?=?f1.value;
????????temp=temp.replace(/\\r/g,"\r");
????????temp=temp.replace(/\\n/g,"\n");
????????result.innerHTML=utf16to8(temp).length;
????}
</script>
</HEAD>
<BODY>
<TEXTAREA?id="f1"?NAME="f1"?ROWS="10"?COLS="50"></TEXTAREA>
<br/>
<INPUT?TYPE="button"?value="count?length"?onclick="count()">
<div?id="result"></div>
</BODY>
</HTML>
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Prefast是一種代碼分析工具，它能夠幫助你找到編譯器不能找到的錯誤或者缺陷。Prefast首次被微軟集成到Visual Studio 2005 Team Suite中去，使用起來非常方便。
2.怎么使用Prefast
在vs2005 Team Suite中，使用Prefast非常簡單。修改你的工程屬性，設置Enable Code Analysis For C/C++為Yes.
效果:
注意到有可能錯誤的地方以淺灰色顯示在編輯器中了。
3.Prefast能幫你找到哪些錯誤
1)沒有初始化
//
no?initial
void ?defect1()
{
???????? int ?a;
???????? int ?b;
????????b? = ?a;
}
void ?defect1()
{
???????? int ?a;
???????? int ?b;
????????b? = ?a;
}
會報: d:\test\testcode\testcode.cpp(18) : warning C6001: Using uninitialized memory 'a': Lines: 15, 16, 18
2)空指針取值
//
one?path?dereference?NULL
void ?defect4( int ?b,? int ?c)
{
???????? int ? * p? = ?NULL;
???????? int ?a? = ? 1 ;
???????? if ?(b? == ? 1 )?{
???????????????? if ?(c? == ? 1 )?{
????????????????????????p? = ? & a;
????????????????}
???????????????? else ?{
????????????????????????????????????????????????
????????????????}
????????}
???????? else ?{
???????????????? if ?(c? == ? 1 )?{
????????????????}
???????????????? else ?{
????????????????????????p? = ? & a;
????????????????}
????????}
???????? * p;
???????? return ;
}????
void ?defect4( int ?b,? int ?c)
{
???????? int ? * p? = ?NULL;
???????? int ?a? = ? 1 ;
???????? if ?(b? == ? 1 )?{
???????????????? if ?(c? == ? 1 )?{
????????????????????????p? = ? & a;
????????????????}
???????????????? else ?{
????????????????????????????????????????????????
????????????????}
????????}
???????? else ?{
???????????????? if ?(c? == ? 1 )?{
????????????????}
???????????????? else ?{
????????????????????????p? = ? & a;
????????????????}
????????}
???????? * p;
???????? return ;
}????
會報:d:\test\testcode\testcode.cpp(65) : warning C6011: Dereferencing NULL pointer 'p': Lines: 45, 46, 48, 57, 65
3)可能錯誤的運算符優先級
void
?defect5()
{
???????? int ?a? = ? 1 ;
???????? int ?b? = ? 1 ;
???????? int ?c? = ? 1 ;
???????? if ?(a? & ?b? == ?c)
???????????????? return ;
}
{
???????? int ?a? = ? 1 ;
???????? int ?b? = ? 1 ;
???????? int ?c? = ? 1 ;
???????? if ?(a? & ?b? == ?c)
???????????????? return ;
}
會報: d:\test\testcode\testcode.cpp(76) : warning C6281: Incorrect order of operations: relational operators have higher precedence than bitwise operators
4)可能的buffer overrun
void
?defect8()
{
???????? char ?buf[ 100 ];
???????? char ?buf2[ 200 ];
???????? int ?i? = ? 100 ;
????????sprintf(buf,? " hello?world?%d " ,?i);
????????strcpy(buf,?buf2);
}
{
???????? char ?buf[ 100 ];
???????? char ?buf2[ 200 ];
???????? int ?i? = ? 100 ;
????????sprintf(buf,? " hello?world?%d " ,?i);
????????strcpy(buf,?buf2);
}
會報: d:\test\testcode\testcode.cpp(133) : warning C6202: Buffer overrun for 'buf', which is possibly stack allocated, in call to 'strcpy': length '200' exceeds buffer size '100'
5)可能的無窮循環
//
infinite?loop
void ?defect14()
{
????????signed? char ?i;
???????? for ?(i? = ? 100 ;?i? >= ? 0 ;?i ++ )?{
????????????????;?
????????}
}
void ?defect14()
{
????????signed? char ?i;
???????? for ?(i? = ? 100 ;?i? >= ? 0 ;?i ++ )?{
????????????????;?
????????}
}
會報: d:\test\testcode\testcode.cpp(198) : warning C6292: Ill-defined for-loop: counts up from maximum
6)格式字符串錯誤
//
Format?string?mismatch
void ?defect21()
{
???????? char ?buff[ 5 ];
????????sprintf(buff,? " %s?%s " ,? " a " );
}
void ?defect21()
{
???????? char ?buff[ 5 ];
????????sprintf(buff,? " %s?%s " ,? " a " );
}
會報: d:\test\testcode\testcode.cpp(277) : warning C6063: Missing string argument to 'sprintf' that corresponds to conversion specifier '2'
7)安全問題
void
?defect27()
{
????????CreateProcess(NULL,
??????????????? " c:\\program?files\\Project.exe?arg1 " ,? // correct?"\"c:\\program?files\\Project.exe\"?arg1",
???????????????NULL,
???????????????NULL,
??????????????? false ,
??????????????? 0 ,
???????????????NULL,
???????????????NULL,
???????????????NULL,
???????????????NULL);???????????????
}
{
????????CreateProcess(NULL,
??????????????? " c:\\program?files\\Project.exe?arg1 " ,? // correct?"\"c:\\program?files\\Project.exe\"?arg1",
???????????????NULL,
???????????????NULL,
??????????????? false ,
??????????????? 0 ,
???????????????NULL,
???????????????NULL,
???????????????NULL,
???????????????NULL);???????????????
}
會報: d:\test\testcode\testcode.cpp(327) : warning C6277: NULL application name with an unquoted path in call to 'CreateProcessA': results in a security vulnerability if the path contains spaces
8)=和==誤用
void
?defect32()
{
???????? int ?a? = ? 1 ;
???????? if ?(a? = ? 2 )
???????????????? return ;
}
{
???????? int ?a? = ? 1 ;
???????? if ?(a? = ? 2 )
???????????????? return ;
}
會報: d:\test\testcode\testcode.cpp(405) : warning C6282: Incorrect operator: assignment of constant in Boolean context. Consider using '==' instead
9)邏輯運算問題
//
always?false
void ?defect45()
{
???????? int ?x;
???????? if ?( 0 ? && ?x ++ )?{
????????????????;
????????}
}
void ?defect45()
{
???????? int ?x;
???????? if ?( 0 ? && ?x ++ )?{
????????????????;
????????}
}
會報: d:\test\testcode\testcode.cpp(564) : warning C6237: (<zero> && <expression>) is always zero. <expression> is never evaluated and might have side effects
10)其他
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