| 1 | /* |
| 2 | * pxheader - program to sit in front of interpreter code to make shell mods |
| 3 | * unnecessary to make Pascal obj's look like real programs. |
| 4 | * |
| 5 | * This program lives in /usr/lib/px_header |
| 6 | * Bill Joy UCB February 6, 1978 |
| 7 | */ |
| 8 | |
| 9 | static char sccsid[] = "@(#)px_header.c 1.3 %G%"; |
| 10 | |
| 11 | #include <stdio.h> |
| 12 | #include <sys/types.h> |
| 13 | #include <a.out.h> |
| 14 | #include "whoami.h" |
| 15 | #include "objfmt.h" |
| 16 | |
| 17 | #define ETXTBSY 26 |
| 18 | #define ADDR_LC HEADER_BYTES - sizeof (struct exec) - sizeof (struct pxhdr) |
| 19 | #define MAXARGS 512 |
| 20 | |
| 21 | extern errno; |
| 22 | |
| 23 | main(argc, argv) |
| 24 | register int argc; |
| 25 | register char *argv[]; |
| 26 | { |
| 27 | register int i; |
| 28 | int codesiz, symtabsiz; |
| 29 | register char *cp; |
| 30 | char *largv[MAXARGS]; |
| 31 | int fd, pv[2], pid; |
| 32 | |
| 33 | cp = (char *)(ADDR_LC); |
| 34 | codesiz = ((struct pxhdr *)(cp))->objsize + sizeof(struct pxhdr); |
| 35 | symtabsiz = ((struct pxhdr *)(cp))->symtabsize; |
| 36 | if (argc > MAXARGS - 3) |
| 37 | error(2, "Too many arguments.\n"); |
| 38 | if (symtabsiz != 0) { |
| 39 | largv[0] = "pxhdr"; |
| 40 | largv[1] = "/tmp/px00000"; |
| 41 | cp = &largv[1][11]; |
| 42 | for (i = getpid(); i > 0; i /= 10) |
| 43 | *cp-- = '0' + i % 10; |
| 44 | fd = creat(largv[1], 0444); |
| 45 | if (fd < 0) |
| 46 | error(3, "Cannot create /tmp file\n"); |
| 47 | for (i = 0; i < argc; i++) |
| 48 | largv[i + 2] = argv[i]; |
| 49 | largv[argc + 2] = 0; |
| 50 | writeobj(fd, codesiz, symtabsiz); |
| 51 | run(PX_DEBUG, largv); |
| 52 | /* no return */ |
| 53 | } |
| 54 | largv[0] = "pipe"; |
| 55 | for (i = 0; i < argc; i++) |
| 56 | largv[i + 1] = argv[i]; |
| 57 | largv[argc + 1] = 0; |
| 58 | pipe(pv); |
| 59 | pid = fork(); |
| 60 | if (pid != 0) { |
| 61 | if (pv[0] != 3) { |
| 62 | close(3); |
| 63 | dup(pv[0]); |
| 64 | close(pv[0]); |
| 65 | } |
| 66 | close(pv[1]); |
| 67 | run(PX_INTRP, largv); |
| 68 | /* no return */ |
| 69 | } |
| 70 | writeobj(pv[1], codesiz, symtabsiz); |
| 71 | exit(0); |
| 72 | } |
| 73 | |
| 74 | writeobj(fd, codesiz, symtabsiz) |
| 75 | int fd; |
| 76 | int codesiz, symtabsiz; |
| 77 | { |
| 78 | int i; |
| 79 | register char *cp; |
| 80 | |
| 81 | cp = (char *)(ADDR_LC); |
| 82 | while (codesiz != 0) { |
| 83 | i = (codesiz < BUFSIZ) ? codesiz : BUFSIZ; |
| 84 | write(fd, cp, i); |
| 85 | cp += i; |
| 86 | codesiz -= i; |
| 87 | } |
| 88 | while (symtabsiz != 0) { |
| 89 | i = (symtabsiz < BUFSIZ) ? symtabsiz : BUFSIZ; |
| 90 | write(fd, cp, i); |
| 91 | cp += i; |
| 92 | symtabsiz -= i; |
| 93 | } |
| 94 | close(fd); |
| 95 | } |
| 96 | |
| 97 | run(prog, args) |
| 98 | char *prog; |
| 99 | char **args; |
| 100 | { |
| 101 | for (;;) { |
| 102 | execv(prog, args); |
| 103 | if (errno != ETXTBSY) |
| 104 | break; |
| 105 | sleep(2); |
| 106 | } |
| 107 | error(0, prog); |
| 108 | error(1, " not found.\n"); |
| 109 | } |
| 110 | |
| 111 | error(errcode, cp) |
| 112 | int errcode; |
| 113 | register char *cp; |
| 114 | { |
| 115 | register int i; |
| 116 | register char *dp; |
| 117 | |
| 118 | dp = cp; |
| 119 | i = 0; |
| 120 | while (*dp++) |
| 121 | i++; |
| 122 | write(2, cp, i); |
| 123 | if (errcode) |
| 124 | exit(errcode); |
| 125 | } |
| 126 | |
| 127 | exit(i) |
| 128 | { |
| 129 | _exit(i); |
| 130 | } |