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gdb步骤,直到源再次可用

gdb

Greg Nisbet · 技术社区 · 6 年前

我在管理GNU grep gdb 在Linux上,单步执行。大约12步后,控制权转移到 setlocale.c ,没有可用的源代码。

示例会话,之后 step 12 没有可用的源代码信息,并且 list 命令只显示文件。

有没有办法 GDB 继续单步执行,直到具有源代码的文件再次可用。或者,是否有一种方法告诉gdb在控制权转移到另一个文件之前保持单步执行?

示例会话,显示源代码最初可用,然后不可用 设置区域设置.c ?

(gdb) start
Temporary breakpoint 1 at 0x402e50: file grep.c, line 2415.
Starting program: ~/ws/opt/grep/out/bin/grep --context=20 -r --line-number --byte-offset --include=\*.c int .
[Thread debugging using libthread_db enabled]
Using host libthread_db library "/lib/x86_64-linux-gnu/libthread_db.so.1".

Temporary breakpoint 1, main (argc=0x8, argv=0x7fffffffdaa8) at grep.c:2415
2415    {
(gdb) l
2410      return result;
2411    }
2412    
2413    int
2414    main (int argc, char **argv)
2415    {
2416      char *keys = NULL;
2417      size_t keycc = 0, oldcc, keyalloc = 0;
2418      int matcher = -1;
2419      bool with_filenames = false;
(gdb) s 12
__GI_setlocale (category=category@entry=0x6, locale=locale@entry=0x420b7b "") at setlocale.c:220
220 setlocale.c: No such file or directory.
(gdb) l
215 in setlocale.c

2 回复 | 直到 6 年前

ks1322 6 年前

finish documentation

Greg Nisbet 6 年前

gdb

source leave_this_file.py leave_this_file

frame 0

MAX_STEPS = 10000


def get_file_name():
    """extract the file name for the bottommost frame"""
    # example string
    #0  main (argc=0x7, argv=0x7fffffffdaa8) at grep.c:2415
    # <source fragment>
    where_str = gdb.execute("frame 0", from_tty=False, to_string=True)
    # last word of first line is file:line
    file_line = where_str.splitlines()[0].split()[-1]
    filename, _, line = file_line.rpartition(":")
    # confirm that line number is an int, raise otherwise
    int(line)
    return filename


def step_out_of_file_once():
    orig_file_name = get_file_name()
    current_file_name = orig_file_name
    counter = 0
    for x in range(MAX_STEPS):
        gdb.execute("step", from_tty=False, to_string=True)
        counter += 1
        current_file_name = get_file_name()
        if orig_file_name != current_file_name:
            break
    print("%s: %30s, %s: %s" % ("new", current_file_name, "steps", counter))


class LeaveThisFile(gdb.Command):
    """step out of the current file"""

    def __init__(self):
        gdb.Command.__init__(
            self, "leave_this_file", gdb.COMMAND_DATA, gdb.COMPLETE_SYMBOL, True
        )

    def invoke(self, arg, from_tty):
        # interpret the arg as a number of times to execute the command
        # 1 by default
        if arg:
            arg = int(arg)
        else:
            arg = 1
        for x in range(arg):
            step_out_of_file_once()


LeaveThisFile()

GNU grep

2415    {
(gdb) startQuit
(gdb) source leave_this_file.py 
(gdb) leave_this_file 15
new:                    setlocale.c, steps: 18
new:        pthread_rwlock_wrlock.c, steps: 8
new: ../sysdeps/unix/sysv/linux/x86/hle.h, steps: 3
new:        pthread_rwlock_wrlock.c, steps: 1
new:                    setlocale.c, steps: 7
new: ../sysdeps/x86_64/multiarch/../strcmp.S, steps: 1
new:                    setlocale.c, steps: 48
new:                       getenv.c, steps: 4
new:     ../sysdeps/x86_64/strlen.S, steps: 2
new:                       getenv.c, steps: 16
new: ../sysdeps/x86_64/multiarch/../strcmp.S, steps: 64
new:                       getenv.c, steps: 53
new:                    setlocale.c, steps: 16
new: ../sysdeps/x86_64/multiarch/../strchr.S, steps: 5
new:                    setlocale.c, steps: 23