mirror of https://gitee.com/openkylin/linux.git
59 lines
840 B
C
59 lines
840 B
C
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/*
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* Copyright 2013-2015, Michael Ellerman, IBM Corp.
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* Licensed under GPLv2.
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*/
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#include <elf.h>
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#include <errno.h>
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#include <fcntl.h>
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#include <link.h>
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#include <stdio.h>
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#include <sys/stat.h>
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#include <sys/types.h>
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#include <unistd.h>
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#include "utils.h"
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static char auxv[4096];
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void *get_auxv_entry(int type)
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{
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ElfW(auxv_t) *p;
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void *result;
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ssize_t num;
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int fd;
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fd = open("/proc/self/auxv", O_RDONLY);
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if (fd == -1) {
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perror("open");
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return NULL;
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}
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result = NULL;
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num = read(fd, auxv, sizeof(auxv));
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if (num < 0) {
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perror("read");
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goto out;
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}
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if (num > sizeof(auxv)) {
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printf("Overflowed auxv buffer\n");
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goto out;
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}
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p = (ElfW(auxv_t) *)auxv;
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while (p->a_type != AT_NULL) {
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if (p->a_type == type) {
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result = (void *)p->a_un.a_val;
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break;
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}
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p++;
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}
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out:
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close(fd);
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return result;
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}
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