nsprpub/tools/tail.c@97036ab72558 (annotated)
nsprpub/tools/tail.c
Tue, 06 Jan 2015 21:39:09 +0100
- author
- Michael Schloh von Bennewitz <michael@schloh.com>
- date
- Tue, 06 Jan 2015 21:39:09 +0100
- branch
- TOR_BUG_9701
- changeset 8
- 97036ab72558
- permissions
- -rw-r--r--
Conditionally force memory storage according to privacy.thirdparty.isolate;
This solves Tor bug #9701, complying with disk avoidance documented in
https://www.torproject.org/projects/torbrowser/design/#disk-avoidance.
| michael@0 | 1 | /* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ |
| michael@0 | 2 | /* This Source Code Form is subject to the terms of the Mozilla Public |
| michael@0 | 3 | * License, v. 2.0. If a copy of the MPL was not distributed with this |
| michael@0 | 4 | * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ |
| michael@0 | 5 | |
| michael@0 | 6 | #include "prio.h" |
| michael@0 | 7 | #include "prprf.h" |
| michael@0 | 8 | #include "prinit.h" |
| michael@0 | 9 | #include "prthread.h" |
| michael@0 | 10 | #include "prinrval.h" |
| michael@0 | 11 | |
| michael@0 | 12 | #include "plerror.h" |
| michael@0 | 13 | #include "plgetopt.h" |
| michael@0 | 14 | |
| michael@0 | 15 | #include <stdlib.h> |
| michael@0 | 16 | |
| michael@0 | 17 | #define BUFFER_SIZE 500 |
| michael@0 | 18 | |
| michael@0 | 19 | static PRFileDesc *out = NULL, *err = NULL; |
| michael@0 | 20 | |
| michael@0 | 21 | static void Help(void) |
| michael@0 | 22 | { |
| michael@0 | 23 | PR_fprintf(err, "Usage: tail [-n <n>] [-f] [-h] <filename>\n"); |
| michael@0 | 24 | PR_fprintf(err, "\t-t <n> Dally time in milliseconds\n"); |
| michael@0 | 25 | PR_fprintf(err, "\t-n <n> Number of bytes before <eof>\n"); |
| michael@0 | 26 | PR_fprintf(err, "\t-f Follow the <eof>\n"); |
| michael@0 | 27 | PR_fprintf(err, "\t-h This message and nothing else\n"); |
| michael@0 | 28 | } /* Help */ |
| michael@0 | 29 | |
| michael@0 | 30 | PRIntn main(PRIntn argc, char **argv) |
| michael@0 | 31 | { |
| michael@0 | 32 | PRIntn rv = 0; |
| michael@0 | 33 | PLOptStatus os; |
| michael@0 | 34 | PRStatus status; |
| michael@0 | 35 | PRFileDesc *file; |
| michael@0 | 36 | PRFileInfo fileInfo; |
| michael@0 | 37 | PRIntervalTime dally; |
| michael@0 | 38 | char buffer[BUFFER_SIZE]; |
| michael@0 | 39 | PRBool follow = PR_FALSE; |
| michael@0 | 40 | const char *filename = NULL; |
| michael@0 | 41 | PRUint32 position = 0, seek = 0, time = 0; |
| michael@0 | 42 | PLOptState *opt = PL_CreateOptState(argc, argv, "hfn:"); |
| michael@0 | 43 | |
| michael@0 | 44 | out = PR_GetSpecialFD(PR_StandardOutput); |
| michael@0 | 45 | err = PR_GetSpecialFD(PR_StandardError); |
| michael@0 | 46 | |
| michael@0 | 47 | while (PL_OPT_EOL != (os = PL_GetNextOpt(opt))) |
| michael@0 | 48 | { |
| michael@0 | 49 | if (PL_OPT_BAD == os) continue; |
| michael@0 | 50 | switch (opt->option) |
| michael@0 | 51 | { |
| michael@0 | 52 | case 0: /* it's the filename */ |
| michael@0 | 53 | filename = opt->value; |
| michael@0 | 54 | break; |
| michael@0 | 55 | case 'n': /* bytes before end of file */ |
| michael@0 | 56 | seek = atoi(opt->value); |
| michael@0 | 57 | break; |
| michael@0 | 58 | case 't': /* dally time */ |
| michael@0 | 59 | time = atoi(opt->value); |
| michael@0 | 60 | break; |
| michael@0 | 61 | case 'f': /* follow the end of file */ |
| michael@0 | 62 | follow = PR_TRUE; |
| michael@0 | 63 | break; |
| michael@0 | 64 | case 'h': /* user wants some guidance */ |
| michael@0 | 65 | Help(); /* so give him an earful */ |
| michael@0 | 66 | return 2; /* but not a lot else */ |
| michael@0 | 67 | break; |
| michael@0 | 68 | default: |
| michael@0 | 69 | break; |
| michael@0 | 70 | } |
| michael@0 | 71 | } |
| michael@0 | 72 | PL_DestroyOptState(opt); |
| michael@0 | 73 | |
| michael@0 | 74 | if (0 == time) time = 1000; |
| michael@0 | 75 | dally = PR_MillisecondsToInterval(time); |
| michael@0 | 76 | |
| michael@0 | 77 | if (NULL == filename) |
| michael@0 | 78 | { |
| michael@0 | 79 | (void)PR_fprintf(out, "Input file not specified\n"); |
| michael@0 | 80 | rv = 1; goto done; |
| michael@0 | 81 | } |
| michael@0 | 82 | file = PR_Open(filename, PR_RDONLY, 0); |
| michael@0 | 83 | if (NULL == file) |
| michael@0 | 84 | { |
| michael@0 | 85 | PL_FPrintError(err, "File cannot be opened for reading"); |
| michael@0 | 86 | return 1; |
| michael@0 | 87 | } |
| michael@0 | 88 | |
| michael@0 | 89 | status = PR_GetOpenFileInfo(file, &fileInfo); |
| michael@0 | 90 | if (PR_FAILURE == status) |
| michael@0 | 91 | { |
| michael@0 | 92 | PL_FPrintError(err, "Cannot acquire status of file"); |
| michael@0 | 93 | rv = 1; goto done; |
| michael@0 | 94 | } |
| michael@0 | 95 | if (seek > 0) |
| michael@0 | 96 | { |
| michael@0 | 97 | if (seek > fileInfo.size) seek = 0; |
| michael@0 | 98 | position = PR_Seek(file, (fileInfo.size - seek), PR_SEEK_SET); |
| michael@0 | 99 | if (-1 == (PRInt32)position) |
| michael@0 | 100 | PL_FPrintError(err, "Cannot seek to starting position"); |
| michael@0 | 101 | } |
| michael@0 | 102 | |
| michael@0 | 103 | do |
| michael@0 | 104 | { |
| michael@0 | 105 | while (position < fileInfo.size) |
| michael@0 | 106 | { |
| michael@0 | 107 | PRInt32 read, bytes = fileInfo.size - position; |
| michael@0 | 108 | if (bytes > sizeof(buffer)) bytes = sizeof(buffer); |
| michael@0 | 109 | read = PR_Read(file, buffer, bytes); |
| michael@0 | 110 | if (read != bytes) |
| michael@0 | 111 | PL_FPrintError(err, "Cannot read to eof"); |
| michael@0 | 112 | position += read; |
| michael@0 | 113 | PR_Write(out, buffer, read); |
| michael@0 | 114 | } |
| michael@0 | 115 | |
| michael@0 | 116 | if (follow) |
| michael@0 | 117 | { |
| michael@0 | 118 | PR_Sleep(dally); |
| michael@0 | 119 | status = PR_GetOpenFileInfo(file, &fileInfo); |
| michael@0 | 120 | if (PR_FAILURE == status) |
| michael@0 | 121 | { |
| michael@0 | 122 | PL_FPrintError(err, "Cannot acquire status of file"); |
| michael@0 | 123 | rv = 1; goto done; |
| michael@0 | 124 | } |
| michael@0 | 125 | } |
| michael@0 | 126 | } while (follow); |
| michael@0 | 127 | |
| michael@0 | 128 | done: |
| michael@0 | 129 | PR_Close(file); |
| michael@0 | 130 | |
| michael@0 | 131 | return rv; |
| michael@0 | 132 | } /* main */ |
| michael@0 | 133 | |
| michael@0 | 134 | /* tail.c */ |
