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编程基础-----c语言打印调用栈

news 来源：原创 2024/5/4 5:48:03

为什么80%的码农都做不了架构师？>>>

官方介绍：

SYNOPSIS top

#include <execinfo.h>

       int backtrace(void **buffer, int size);

       char **backtrace_symbols(void *const *buffer, int size);

       void backtrace_symbols_fd(void *const *buffer, int size, int fd);

DESCRIPTION top

backtrace() returns a backtrace for the calling program, in the array
       pointed to by buffer.  A backtrace is the series of currently active
       function calls for the program.  Each item in the array pointed to by
       buffer is of type void *, and is the return address from the
       corresponding stack frame.  The size argument specifies the maximum
       number of addresses that can be stored in buffer.  If the backtrace
       is larger than size, then the addresses corresponding to the size
       most recent function calls are returned; to obtain the complete
       backtrace, make sure that buffer and size are large enough.

       Given the set of addresses returned by backtrace() in buffer,
       backtrace_symbols() translates the addresses into an array of strings
       that describe the addresses symbolically.  The size argument
       specifies the number of addresses in buffer.  The symbolic
       representation of each address consists of the function name (if this
       can be determined), a hexadecimal offset into the function, and the
       actual return address (in hexadecimal).  The address of the array of
       string pointers is returned as the function result of
       backtrace_symbols().  This array is malloc(3)ed by
       backtrace_symbols(), and must be freed by the caller.  (The strings
       pointed to by the array of pointers need not and should not be
       freed.)

       backtrace_symbols_fd() takes the same buffer and size arguments as
       backtrace_symbols(), but instead of returning an array of strings to
       the caller, it writes the strings, one per line, to the file
       descriptor fd.  backtrace_symbols_fd() does not call malloc(3), and
       so can be employed in situations where the latter function might
       fail.

RETURN VALUE top

backtrace() returns the number of addresses returned in buffer, which
       is not greater than size.  If the return value is less than size,
       then the full backtrace was stored; if it is equal to size, then it
       may have been truncated, in which case the addresses of the oldest
       stack frames are not returned.

       On success, backtrace_symbols() returns a pointer to the array
       malloc(3)ed by the call; on error, NULL is returned.

VERSIONS top

backtrace(), backtrace_symbols(), and backtrace_symbols_fd() are
       provided in glibc since version 2.1.

CONFORMING TO top

These functions are GNU extensions.

NOTES top

These functions make some assumptions about how a function's return
       address is stored on the stack.  Note the following:

       *  Omission of the frame pointers (as implied by any of gcc(1)'s
          nonzero optimization levels) may cause these assumptions to be
          violated.

       *  Inlined functions do not have stack frames.

       *  Tail-call optimization causes one stack frame to replace another.

       The symbol names may be unavailable without the use of special linker
       options.  For systems using the GNU linker, it is necessary to use
       the -rdynamic linker option.  Note that names of "static" functions
       are not exposed, and won't be available in the backtrace.

EXAMPLE top

The program below demonstrates the use of backtrace() and
       backtrace_symbols().  The following shell session shows what we might
       see when running the program:

           $ cc -rdynamic prog.c -o prog
           $ ./prog 3
           backtrace() returned 8 addresses
           ./prog(myfunc3+0x5c) [0x80487f0]
           ./prog [0x8048871]
           ./prog(myfunc+0x21) [0x8048894]
           ./prog(myfunc+0x1a) [0x804888d]
           ./prog(myfunc+0x1a) [0x804888d]
           ./prog(main+0x65) [0x80488fb]
           /lib/libc.so.6(__libc_start_main+0xdc) [0xb7e38f9c]
           ./prog [0x8048711]

Program source

#include <execinfo.h>
       #include <stdio.h>
       #include <stdlib.h>
       #include <unistd.h>

       void
       myfunc3(void)
       {
           int j, nptrs;
       #define SIZE 100
           void *buffer[100];
           char **strings;

           nptrs = backtrace(buffer, SIZE);
           printf("backtrace() returned %d addresses\n", nptrs);

           /* The call backtrace_symbols_fd(buffer, nptrs, STDOUT_FILENO)
              would produce similar output to the following: */

           strings = backtrace_symbols(buffer, nptrs);
           if (strings == NULL) {
               perror("backtrace_symbols");
               exit(EXIT_FAILURE);
           }

           for (j = 0; j < nptrs; j++)
               printf("%s\n", strings[j]);

           free(strings);
       }

       static void   /* "static" means don't export the symbol... */
       myfunc2(void)
       {
           myfunc3();
       }

       void
       myfunc(int ncalls)
       {
           if (ncalls > 1)
               myfunc(ncalls - 1);
           else
               myfunc2();
       }

       int
       main(int argc, char *argv[])
       {
           if (argc != 2) {
               fprintf(stderr, "%s num-calls\n", argv[0]);
               exit(EXIT_FAILURE);
           }

           myfunc(atoi(argv[1]));
           exit(EXIT_SUCCESS);
       }

自己示例：

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