46 lines
829 B
C
46 lines
829 B
C
/*
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newroot.c
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Replace the current root with a new one
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*/
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#include <errno.h>
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#include <stdio.h>
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#include <stdlib.h>
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#include <string.h>
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#include <sys/mount.h>
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void usage(void) {
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fprintf(stderr, "Usage: newroot [-i] <block-special>\n");
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fprintf(stderr, "-i: copy mfs binary from boot image to memory\n");
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exit(1);
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}
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int main(int argc, char *argv[])
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{
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int r;
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char *dev;
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int mountflags;
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r = 0;
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mountflags = 0; /* !read-only */
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if (argc != 2 && argc != 3) usage();
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if(argc == 2) {
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dev = argv[1];
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} else if(argc == 3) {
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/* -i flag was supposedly entered. Verify.*/
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if(strcmp(argv[1], "-i") != 0) usage();
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mountflags |= MS_REUSE;
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dev = argv[2];
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}
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r = mount(dev, "/", mountflags, NULL, NULL);
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if (r != 0) {
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fprintf(stderr, "newroot: mount failed: %s\n",strerror(errno));
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exit(1);
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}
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return 0;
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}
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