projects / unix-history / blame
| Commit | Line | Data |
|---|---|---|
| 96df40f3 CR |
1 | #ifdef MFS |
| 2 | ||
| 3 | #include <stdlib.h> | |
| 4 | #include <unistd.h> | |
| 5 | #include <stdio.h> | |
| 6 | #include <sys/types.h> | |
| 7 | #include <sys/errno.h> | |
| 8 | #include <sys/signal.h> | |
| 9 | #include <sys/file.h> | |
| 10 | #include <sys/stat.h> | |
| 11 | #include <sys/mman.h> | |
| 12 | #include <sys/mount.h> | |
| 13 | ||
| 14 | ||
| 15 | ||
| 16 | static void | |
| 17 | sighandler() | |
| 18 | { | |
| 19 | /* | |
| 20 | * kernel notifies us that the FS has been mounted successfully. | |
| 21 | */ | |
| 22 | exit(0); | |
| 23 | } | |
| 24 | ||
| 25 | ||
| 26 | void | |
| 27 | mfs_mount(addr, len, name, dir, flags) | |
| 28 | caddr_t addr; | |
| 29 | unsigned long len; | |
| 30 | char *name, *dir; | |
| 31 | int flags; | |
| 32 | { | |
| 33 | struct mfs_args margs; | |
| 34 | char nmbuf[16]; | |
| 35 | int pfeife[2]; | |
| 36 | char buf[1024]; | |
| 37 | int red; | |
| 38 | ||
| 39 | ||
| 40 | ||
| 41 | signal(SIGUSR1, sighandler); | |
| 42 | if (pipe(pfeife) == -1) | |
| 43 | fatal("cannot create pipe: %s", strerror(errno)); | |
| 44 | switch (fork()) { | |
| 45 | case -1: | |
| 46 | fatal("cannot fork: %s", strerror(errno)); | |
| 47 | case 0: | |
| 48 | /* | |
| 49 | * child: disassociate from controlling terminal, | |
| 50 | * and mount the filesystem. | |
| 51 | */ | |
| 52 | dup2(pfeife[1], 2); | |
| 53 | close(0); | |
| 54 | close(1); | |
| 55 | if (pfeife[0] != 2) close(pfeife[0]); | |
| 56 | if (pfeife[1] != 2) close(pfeife[1]); | |
| 57 | setsid(); | |
| 58 | (void)chdir("/"); | |
| 59 | if (name == 0) { | |
| 60 | sprintf(nmbuf, "MFS:%d", getpid()); | |
| 61 | name = nmbuf; | |
| 62 | } | |
| 63 | margs.name = name; | |
| 64 | margs.base = addr; | |
| 65 | margs.size = len; | |
| 66 | margs.flags = MFSMNT_SIGPPID; | |
| 67 | if (mount(MOUNT_MFS, dir, flags, &margs) == -1) | |
| 68 | fatal("mounting MFS: %s", strerror(errno)); | |
| 69 | default: | |
| 70 | /* | |
| 71 | * parent; if the mount system call fails, the | |
| 72 | * child will write error messages to the pipe. | |
| 73 | * We duplicate those messages to our stdout. | |
| 74 | * If the mount succeedet, we will receive a SIGUSR1 | |
| 75 | * (and exit with status 0). | |
| 76 | */ | |
| 77 | close(pfeife[1]); | |
| 78 | while ((red = read(pfeife[0], buf, sizeof(buf))) > 0) | |
| 79 | write(2, buf, red); | |
| 80 | exit(1); | |
| 81 | } | |
| 82 | /* NOTREACHED */ | |
| 83 | } | |
| 84 | ||
| 85 | ||
| 86 | caddr_t | |
| 87 | mfs_malloc(size) | |
| 88 | unsigned long size; | |
| 89 | { | |
| 90 | caddr_t addr; | |
| 91 | ||
| 92 | addr = mmap(0, size, PROT_READ | PROT_WRITE, | |
| 93 | MAP_ANON | MAP_SHARED, -1, 0); | |
| 94 | if (addr == (caddr_t)-1) | |
| 95 | fatal("cannot allocate memory: %s", strerror(errno)); | |
| 96 | return(addr); | |
| 97 | } | |
| 98 | ||
| 99 | void | |
| 100 | mfs_mountfile(file, dir, flags) | |
| 101 | char *file, *dir; | |
| 102 | int flags; | |
| 103 | { | |
| 104 | caddr_t addr; | |
| 105 | int fd; | |
| 106 | struct stat st; | |
| 107 | ||
| 108 | ||
| 109 | fd = open(file, O_RDWR | O_EXLOCK); | |
| 110 | if ((fd == -1) || (fstat(fd, &st) == -1)) | |
| 111 | fatal("%s: %s", file, strerror(errno)); | |
| 112 | addr = mmap(0, st.st_size, PROT_READ | PROT_WRITE, | |
| 113 | MAP_FILE | MAP_SHARED, fd, 0); | |
| 114 | if (addr == (caddr_t) -1) | |
| 115 | fatal("cannot mmap file: %s", strerror(errno)); | |
| 116 | mfs_mount(addr, st.st_size, file, dir, flags); | |
| 117 | } | |
| 118 | ||
| 119 | #else | |
| 120 | caddr_t | |
| 121 | mfs_malloc() | |
| 122 | { | |
| 123 | fatal("compiled without MFS support"); | |
| 124 | return(0); | |
| 125 | } | |
| 126 | void mfs_mount() {} | |
| 127 | void mfs_mountfile() {mfs_malloc();} | |
| 128 | #endif |