source: mainline/uspace/app/bdsh/cmds/modules/cat/cat.c@ e367f5b8

lfn serial ticket/834-toolchain-update topic/msim-upgrade topic/simplify-dev-export
Last change on this file since e367f5b8 was cc9f314, checked in by Vojtech Horky <vojtechhorky@…>, 13 years ago

Implement head and tail functionality in bdsh/cat (thx Taylor Killian)

This patch fixes a number of problems in the cat app. Most
importantly, it correctly displays characters at the end of the read
buffer, where previously multibyte characters were being rendered as
U_SPECIAL. It also implements the buffer size argument (-b) that the
—help mentions. The size of the buffer must be at least 4 though in
order to accommodate multibyte characters. Finally head (-H) and tail
(-t) were implemented as per —help.
  • Property mode set to 100644
File size: 8.7 KB
Line 
1/*
2 * Copyright (c) 2008 Tim Post
3 * Copyright (c) 2011, Martin Sucha
4 * All rights reserved.
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
8 * are met:
9 *
10 * - Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * - Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 * - The name of the author may not be used to endorse or promote products
16 * derived from this software without specific prior written permission.
17 *
18 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
19 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
20 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
21 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
22 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
23 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
24 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
25 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
26 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
27 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
28 */
29
30#include <stdio.h>
31#include <stdlib.h>
32#include <unistd.h>
33#include <getopt.h>
34#include <str.h>
35#include <fcntl.h>
36#include <io/console.h>
37#include <io/color.h>
38#include <io/style.h>
39#include <io/keycode.h>
40#include <errno.h>
41#include <vfs/vfs.h>
42#include <assert.h>
43
44#include "config.h"
45#include "util.h"
46#include "errors.h"
47#include "entry.h"
48#include "cat.h"
49#include "cmds.h"
50
51static const char *cmdname = "cat";
52#define CAT_VERSION "0.0.1"
53#define CAT_DEFAULT_BUFLEN 1024
54#define CAT_FULL_FILE 0
55
56static const char *hexchars = "0123456789abcdef";
57
58static bool paging_enabled = false;
59static size_t chars_remaining = 0;
60static size_t lines_remaining = 0;
61static sysarg_t console_cols = 0;
62static sysarg_t console_rows = 0;
63static bool should_quit = false;
64
65static console_ctrl_t *console = NULL;
66
67static struct option const long_options[] = {
68 { "help", no_argument, 0, 'h' },
69 { "version", no_argument, 0, 'v' },
70 { "head", required_argument, 0, 'H' },
71 { "tail", required_argument, 0, 't' },
72 { "buffer", required_argument, 0, 'b' },
73 { "more", no_argument, 0, 'm' },
74 { "hex", no_argument, 0, 'x' },
75 { 0, 0, 0, 0 }
76};
77
78/* Dispays help for cat in various levels */
79void help_cmd_cat(unsigned int level)
80{
81 if (level == HELP_SHORT) {
82 printf("`%s' shows the contents of files\n", cmdname);
83 } else {
84 help_cmd_cat(HELP_SHORT);
85 printf(
86 "Usage: %s [options] <file1> [file2] [...]\n"
87 "Options:\n"
88 " -h, --help A short option summary\n"
89 " -v, --version Print version information and exit\n"
90 " -H, --head ## Print only the first ## bytes\n"
91 " -t, --tail ## Print only the last ## bytes\n"
92 " -b, --buffer ## Set the read buffer size to ##\n"
93 " -m, --more Pause after each screen full\n"
94 " -x, --hex Print bytes as hex values\n"
95 "Currently, %s is under development, some options don't work.\n",
96 cmdname, cmdname);
97 }
98
99 return;
100}
101
102static void waitprompt()
103{
104 console_set_pos(console, 0, console_rows-1);
105 console_set_color(console, COLOR_WHITE, COLOR_BLUE, 0);
106
107 printf("ENTER/SPACE/PAGE DOWN - next page, "
108 "ESC/Q - quit, C - continue unpaged");
109 fflush(stdout);
110
111 console_set_style(console, STYLE_NORMAL);
112}
113
114static void waitkey()
115{
116 kbd_event_t ev;
117
118 while (true) {
119 if (!console_get_kbd_event(console, &ev)) {
120 return;
121 }
122 if (ev.type == KEY_PRESS) {
123 if (ev.key == KC_ESCAPE || ev.key == KC_Q) {
124 should_quit = true;
125 return;
126 }
127 if (ev.key == KC_C) {
128 paging_enabled = false;
129 return;
130 }
131 if (ev.key == KC_ENTER || ev.key == KC_SPACE ||
132 ev.key == KC_PAGE_DOWN) {
133 return;
134 }
135 }
136 }
137 assert(false);
138}
139
140static void newpage()
141{
142 console_clear(console);
143 chars_remaining = console_cols;
144 lines_remaining = console_rows - 1;
145}
146
147static void paged_char(wchar_t c)
148{
149 putchar(c);
150 if (paging_enabled) {
151 chars_remaining--;
152 if (c == '\n' || chars_remaining == 0) {
153 chars_remaining = console_cols;
154 lines_remaining--;
155 }
156 if (lines_remaining == 0) {
157 fflush(stdout);
158 waitprompt();
159 waitkey();
160 newpage();
161 }
162 }
163}
164
165static unsigned int cat_file(const char *fname, size_t blen, bool hex,
166 off64_t head, off64_t tail, bool tail_first)
167{
168 int fd, bytes = 0, count = 0, reads = 0;
169 char *buff = NULL;
170 int i;
171 size_t offset = 0, copied_bytes = 0;
172 off64_t file_size = 0, length = 0;
173
174 fd = open(fname, O_RDONLY);
175 if (fd < 0) {
176 printf("Unable to open %s\n", fname);
177 return 1;
178 }
179
180 if (NULL == (buff = (char *) malloc(blen + 1))) {
181 close(fd);
182 printf("Unable to allocate enough memory to read %s\n",
183 fname);
184 return 1;
185 }
186
187 if (tail != CAT_FULL_FILE) {
188 file_size = lseek(fd, 0, SEEK_END);
189 if (head == CAT_FULL_FILE) {
190 head = file_size;
191 length = tail;
192 } else if (tail_first) {
193 length = head;
194 } else {
195 if (tail > head)
196 tail = head;
197 length = tail;
198 }
199
200 if (tail_first) {
201 lseek(fd, (tail >= file_size) ? 0 : (file_size - tail), SEEK_SET);
202 } else {
203 lseek(fd, ((head - tail) >= file_size) ? 0 : (head - tail), SEEK_SET);
204 }
205 } else
206 length = head;
207
208 do {
209 bytes = read(fd, buff + copied_bytes, (
210 (length != CAT_FULL_FILE && length - (off64_t)count <= (off64_t)(blen - copied_bytes)) ?
211 (size_t)(length - count) :
212 (blen - copied_bytes) ) );
213 bytes += copied_bytes;
214 copied_bytes = 0;
215
216 if (bytes > 0) {
217 buff[bytes] = '\0';
218 offset = 0;
219 for (i = 0; i < bytes && !should_quit; i++) {
220 if (hex) {
221 paged_char(hexchars[((uint8_t)buff[i])/16]);
222 paged_char(hexchars[((uint8_t)buff[i])%16]);
223 paged_char(((count+i+1) & 0xf) == 0 ? '\n' : ' ');
224 }
225 else {
226 wchar_t c = str_decode(buff, &offset, bytes);
227 if (c == 0) {
228 /* Reached end of string */
229 break;
230 } else if (c == U_SPECIAL && offset + 2 >= (size_t)bytes) {
231 /* If an extended character is cut off due to the size of the buffer,
232 we will copy it over to the next buffer so it can be read correctly. */
233 copied_bytes = bytes - offset + 1;
234 memcpy(buff, buff + offset - 1, copied_bytes);
235 break;
236 }
237 paged_char(c);
238 }
239
240 }
241 count += bytes;
242 reads++;
243 }
244 } while (bytes > 0 && !should_quit && (count < length || length == CAT_FULL_FILE));
245
246 close(fd);
247 if (bytes == -1) {
248 printf("Error reading %s\n", fname);
249 free(buff);
250 return 1;
251 }
252
253 free(buff);
254
255 return 0;
256}
257
258/* Main entry point for cat, accepts an array of arguments */
259int cmd_cat(char **argv)
260{
261 unsigned int argc, i, ret = 0;
262 size_t buffer = 0;
263 int c, opt_ind;
264 aoff64_t head = CAT_FULL_FILE, tail = CAT_FULL_FILE;
265 bool hex = false;
266 bool more = false;
267 bool tailFirst = false;
268 sysarg_t rows, cols;
269 int rc;
270
271 /*
272 * reset global state
273 * TODO: move to structure?
274 */
275 paging_enabled = false;
276 chars_remaining = 0;
277 lines_remaining = 0;
278 console_cols = 0;
279 console_rows = 0;
280 should_quit = false;
281 console = console_init(stdin, stdout);
282
283 argc = cli_count_args(argv);
284
285 for (c = 0, optind = 0, opt_ind = 0; c != -1;) {
286 c = getopt_long(argc, argv, "xhvmH:t:b:", long_options, &opt_ind);
287 switch (c) {
288 case 'h':
289 help_cmd_cat(HELP_LONG);
290 return CMD_SUCCESS;
291 case 'v':
292 printf("%s\n", CAT_VERSION);
293 return CMD_SUCCESS;
294 case 'H':
295 if (!optarg || str_uint64_t(optarg, NULL, 10, false, &head) != EOK ) {
296 puts("Invalid head size\n");
297 return CMD_FAILURE;
298 }
299 break;
300 case 't':
301 if (!optarg || str_uint64_t(optarg, NULL, 10, false, &tail) != EOK ) {
302 puts("Invalid tail size\n");
303 return CMD_FAILURE;
304 }
305 if (head == CAT_FULL_FILE)
306 tailFirst = true;
307 break;
308 case 'b':
309 if (!optarg || str_size_t(optarg, NULL, 10, false, &buffer) != EOK ) {
310 puts("Invalid buffer size\n");
311 return CMD_FAILURE;
312 }
313 break;
314 case 'm':
315 more = true;
316 break;
317 case 'x':
318 hex = true;
319 break;
320 }
321 }
322
323 argc -= optind;
324
325 if (argc < 1) {
326 printf("%s - incorrect number of arguments. Try `%s --help'\n",
327 cmdname, cmdname);
328 return CMD_FAILURE;
329 }
330
331 if (buffer < 4)
332 buffer = CAT_DEFAULT_BUFLEN;
333
334 if (more) {
335 rc = console_get_size(console, &cols, &rows);
336 if (rc != EOK) {
337 printf("%s - cannot get console size\n", cmdname);
338 return CMD_FAILURE;
339 }
340 console_cols = cols;
341 console_rows = rows;
342 paging_enabled = true;
343 newpage();
344 }
345
346 for (i = optind; argv[i] != NULL && !should_quit; i++)
347 ret += cat_file(argv[i], buffer, hex, head, tail, tailFirst);
348
349 if (ret)
350 return CMD_FAILURE;
351 else
352 return CMD_SUCCESS;
353}
354
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