| 1 | /* |
| 2 | * CMUCS AFStools |
| 3 | * dumpscan - routines for scanning and manipulating AFS volume dumps |
| 4 | * |
| 5 | * Copyright (c) 1998 Carnegie Mellon University |
| 6 | * All Rights Reserved. |
| 7 | * |
| 8 | * Permission to use, copy, modify and distribute this software and its |
| 9 | * documentation is hereby granted, provided that both the copyright |
| 10 | * notice and this permission notice appear in all copies of the |
| 11 | * software, derivative works or modified versions, and any portions |
| 12 | * thereof, and that both notices appear in supporting documentation. |
| 13 | * |
| 14 | * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS" |
| 15 | * CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR |
| 16 | * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE. |
| 17 | * |
| 18 | * Carnegie Mellon requests users of this software to return to |
| 19 | * |
| 20 | * Software Distribution Coordinator or Software_Distribution@CS.CMU.EDU |
| 21 | * School of Computer Science |
| 22 | * Carnegie Mellon University |
| 23 | * Pittsburgh PA 15213-3890 |
| 24 | * |
| 25 | * any improvements or extensions that they make and grant Carnegie Mellon |
| 26 | * the rights to redistribute these changes. |
| 27 | */ |
| 28 | |
| 29 | /* xf_files.c - XFILE routines for accessing UNIX files */ |
| 30 | |
| 31 | #include <sys/types.h> |
| 32 | #include <sys/stat.h> |
| 33 | #include <fcntl.h> |
| 34 | #include <errno.h> |
| 35 | #include <stdlib.h> |
| 36 | #include <string.h> |
| 37 | #include <stdio.h> |
| 38 | #include <unistd.h> |
| 39 | |
| 40 | #include "xfiles.h" |
| 41 | #include "xf_errs.h" |
| 42 | |
| 43 | #define O_MODE_MASK (O_RDONLY | O_WRONLY | O_RDWR) |
| 44 | |
| 45 | |
| 46 | /* do_read for stdio xfiles */ |
| 47 | static afs_uint32 |
| 48 | xf_FILE_do_read(XFILE * X, void *buf, afs_uint32 count) |
| 49 | { |
| 50 | FILE *F = X->refcon; |
| 51 | |
| 52 | /* XXX: handle short and interrupted reads */ |
| 53 | if (fread(buf, count, 1, F) != 1) |
| 54 | return ferror(F) ? errno : ERROR_XFILE_EOF; |
| 55 | return 0; |
| 56 | } |
| 57 | |
| 58 | |
| 59 | /* do_write for stdio xfiles */ |
| 60 | static afs_uint32 |
| 61 | xf_FILE_do_write(XFILE * X, void *buf, afs_uint32 count) |
| 62 | { |
| 63 | FILE *F = X->refcon; |
| 64 | |
| 65 | /* XXX: handle interrupted writes */ |
| 66 | if (fwrite(buf, count, 1, F) != 1) |
| 67 | return errno; |
| 68 | return 0; |
| 69 | } |
| 70 | |
| 71 | |
| 72 | /* do_tell for stdio xfiles */ |
| 73 | static afs_uint32 |
| 74 | xf_FILE_do_tell(XFILE * X, dt_uint64 * offset) |
| 75 | { |
| 76 | FILE *F = X->refcon; |
| 77 | off_t where; |
| 78 | |
| 79 | where = ftell(F); |
| 80 | if (where == -1) |
| 81 | return errno; |
| 82 | set64(*offset, where); |
| 83 | return 0; |
| 84 | } |
| 85 | |
| 86 | |
| 87 | /* do_seek for stdio xfiles */ |
| 88 | static afs_uint32 |
| 89 | xf_FILE_do_seek(XFILE * X, dt_uint64 * offset) |
| 90 | { |
| 91 | FILE *F = X->refcon; |
| 92 | off_t where = get64(*offset); |
| 93 | |
| 94 | if (fseek(F, where, SEEK_SET) == -1) |
| 95 | return errno; |
| 96 | return 0; |
| 97 | } |
| 98 | |
| 99 | |
| 100 | /* do_skip for stdio xfiles */ |
| 101 | static afs_uint32 |
| 102 | xf_FILE_do_skip(XFILE * X, afs_uint32 count) |
| 103 | { |
| 104 | FILE *F = X->refcon; |
| 105 | |
| 106 | if (fseek(F, count, SEEK_CUR) == -1) |
| 107 | return errno; |
| 108 | return 0; |
| 109 | } |
| 110 | |
| 111 | |
| 112 | /* do_close for stdio xfiles */ |
| 113 | static afs_uint32 |
| 114 | xf_FILE_do_close(XFILE * X) |
| 115 | { |
| 116 | FILE *F = X->refcon; |
| 117 | |
| 118 | X->refcon = 0; |
| 119 | if (fclose(F)) |
| 120 | return errno; |
| 121 | return 0; |
| 122 | } |
| 123 | |
| 124 | |
| 125 | /* Prepare a stdio XFILE */ |
| 126 | static void |
| 127 | prepare(XFILE * X, FILE * F, int xflag) |
| 128 | { |
| 129 | struct stat st; |
| 130 | |
| 131 | memset(X, 0, sizeof(*X)); |
| 132 | X->do_read = xf_FILE_do_read; |
| 133 | X->do_write = xf_FILE_do_write; |
| 134 | X->do_tell = xf_FILE_do_tell; |
| 135 | X->do_close = xf_FILE_do_close; |
| 136 | X->refcon = F; |
| 137 | if (xflag == O_RDWR) |
| 138 | X->is_writable = 1; |
| 139 | |
| 140 | if (!fstat(fileno(F), &st) |
| 141 | && ((st.st_mode & S_IFMT) == S_IFREG |
| 142 | || (st.st_mode & S_IFMT) == S_IFBLK)) { |
| 143 | X->is_seekable = 1; |
| 144 | X->do_seek = xf_FILE_do_seek; |
| 145 | X->do_skip = xf_FILE_do_skip; |
| 146 | } |
| 147 | } |
| 148 | |
| 149 | |
| 150 | /* Open an XFILE by path */ |
| 151 | afs_uint32 |
| 152 | xfopen_path(XFILE * X, int flag, char *path, int mode) |
| 153 | { |
| 154 | FILE *F = 0; |
| 155 | int fd = -1, xflag; |
| 156 | afs_uint32 code; |
| 157 | |
| 158 | xflag = flag & O_MODE_MASK; |
| 159 | if (xflag == O_WRONLY) |
| 160 | return ERROR_XFILE_WRONLY; |
| 161 | |
| 162 | if ((fd = open(path, flag, mode)) < 0) |
| 163 | return errno; |
| 164 | if (!(F = fdopen(fd, (xflag == O_RDONLY) ? "r" : "r+"))) { |
| 165 | code = errno; |
| 166 | close(fd); |
| 167 | return code; |
| 168 | } |
| 169 | |
| 170 | prepare(X, F, xflag); |
| 171 | return 0; |
| 172 | } |
| 173 | |
| 174 | |
| 175 | /* Open an XFILE by FILE * */ |
| 176 | afs_uint32 |
| 177 | xfopen_FILE(XFILE * X, int flag, FILE * F) |
| 178 | { |
| 179 | flag &= O_MODE_MASK; |
| 180 | if (flag == O_WRONLY) |
| 181 | return ERROR_XFILE_WRONLY; |
| 182 | prepare(X, F, flag); |
| 183 | return 0; |
| 184 | } |
| 185 | |
| 186 | |
| 187 | /* Open an XFILE by file descriptor */ |
| 188 | afs_uint32 |
| 189 | xfopen_fd(XFILE * X, int flag, int fd) |
| 190 | { |
| 191 | FILE *F; |
| 192 | |
| 193 | flag &= O_MODE_MASK; |
| 194 | if (flag == O_WRONLY) |
| 195 | return ERROR_XFILE_WRONLY; |
| 196 | if (!(F = fdopen(fd, (flag == O_RDONLY) ? "r" : "r+"))) |
| 197 | return errno; |
| 198 | prepare(X, F, flag); |
| 199 | return 0; |
| 200 | } |
| 201 | |
| 202 | |
| 203 | /* open-by-name support for filenames */ |
| 204 | afs_uint32 |
| 205 | xfon_path(XFILE * X, int flag, char *name) |
| 206 | { |
| 207 | return xfopen_path(X, flag, name, 0644); |
| 208 | } |
| 209 | |
| 210 | |
| 211 | /* open-by-name support for file descriptors */ |
| 212 | afs_uint32 |
| 213 | xfon_fd(XFILE * X, int flag, char *name) |
| 214 | { |
| 215 | int fd = atoi(name); |
| 216 | return xfopen_fd(X, flag, fd); |
| 217 | } |
| 218 | |
| 219 | |
| 220 | /* open-by-name support for standard I/O */ |
| 221 | afs_uint32 |
| 222 | xfon_stdio(XFILE * X, int flag) |
| 223 | { |
| 224 | flag &= O_MODE_MASK; |
| 225 | if (flag == O_WRONLY) |
| 226 | flag = O_RDWR; |
| 227 | return xfopen_FILE(X, flag, (flag == O_RDONLY) ? stdin : stdout); |
| 228 | } |