ref: 1ccd0cd04d75840861e26f6c5f6ac73396d43d8a
dir: /sys/src/cmd/strip.c/
#include <u.h> #include <libc.h> #include <bio.h> #include <mach.h> void error(char* fmt, ...) { va_list arg; char *e, s[256]; va_start(arg, fmt); e = seprint(s, s+sizeof(s), "%s: ", argv0); e = vseprint(e, s+sizeof(s), fmt, arg); e = seprint(e, s+sizeof(s), "\n"); va_end(arg); write(2, s, e-s); } static void usage(void) { error("usage: %s -o ofile file\n\t%s file ...\n", argv0, argv0); exits("usage"); } static int strip(char* file, char* out) { Dir *dir; int fd, i; Fhdr fhdr; Exec *exec; ulong mode; void *data; vlong length; if((fd = open(file, OREAD)) < 0){ error("%s: open: %r", file); return 1; } if(!crackhdr(fd, &fhdr)){ error("%s: %r", file); close(fd); return 1; } for(i = MIN_MAGIC; i <= MAX_MAGIC; i++){ if(fhdr.magic == _MAGIC(0, i) || fhdr.magic == _MAGIC(HDR_MAGIC, i)) break; } if(i > MAX_MAGIC){ error("%s: not a recognizeable binary", file); close(fd); return 1; } if((dir = dirfstat(fd)) == nil){ error("%s: stat: %r", file); close(fd); return 1; } length = fhdr.datoff+fhdr.datsz; if(length == dir->length){ if(out == nil){ /* nothing to do */ error("%s: already stripped", file); free(dir); close(fd); return 0; } } if(length > dir->length){ error("%s: strange length", file); close(fd); free(dir); return 1; } mode = dir->mode; free(dir); if((data = malloc(length)) == nil){ error("%s: malloc failure", file); close(fd); return 1; } seek(fd, 0LL, 0); if(read(fd, data, length) != length){ error("%s: read: %r", file); close(fd); free(data); return 1; } close(fd); exec = data; exec->syms = 0; exec->spsz = 0; exec->pcsz = 0; if(out == nil){ if(remove(file) < 0) { error("%s: remove: %r", file); free(data); return 1; } out = file; } if((fd = create(out, OWRITE, mode)) < 0){ error("%s: create: %r", out); free(data); return 1; } if(write(fd, data, length) != length){ error("%s: write: %r", out); close(fd); free(data); return 1; } close(fd); free(data); return 0; } void main(int argc, char* argv[]) { int r; char *p; p = nil; ARGBEGIN{ default: usage(); break; case 'o': p = ARGF(); if(p == nil) usage(); break; }ARGEND; switch(argc){ case 0: usage(); return; case 1: if(p != nil){ r = strip(*argv, p); break; } /*FALLTHROUGH*/ default: r = 0; while(argc > 0){ r |= strip(*argv, nil); argc--; argv++; } break; } if(r) exits("error"); exits(0); }