Fix typo in german translation.
[maemo-rb.git] / apps / plugins / sort.c
blobf3ea5f0a3d43ef1fceb130954fcce55582b2604f
1 /***************************************************************************
2 * __________ __ ___.
3 * Open \______ \ ____ ____ | | _\_ |__ _______ ___
4 * Source | _// _ \_/ ___\| |/ /| __ \ / _ \ \/ /
5 * Jukebox | | ( <_> ) \___| < | \_\ ( <_> > < <
6 * Firmware |____|_ /\____/ \___ >__|_ \|___ /\____/__/\_ \
7 * \/ \/ \/ \/ \/
8 * $Id$
10 * Copyright (C) 2002 Linus Nielsen Feltzing
12 * This program is free software; you can redistribute it and/or
13 * modify it under the terms of the GNU General Public License
14 * as published by the Free Software Foundation; either version 2
15 * of the License, or (at your option) any later version.
17 * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
18 * KIND, either express or implied.
20 ****************************************************************************/
21 #include "plugin.h"
23 /****************************************************************************
24 * Buffer handling:
26 * We allocate the MP3 buffer for storing the text to be sorted, and then
27 * search the buffer for newlines and store an array of character pointers
28 * to the strings.
30 * The pointer array grows from the top of the buffer and downwards:
32 * |-------------|
33 * | pointers[2] |--------|
34 * | pointers[1] |------| |
35 * | pointers[0] |----| | |
36 * |-------------| | | |
37 * | | | | |
38 * | | | | |
39 * | free space | | | |
40 * | | | | |
41 * | | | | |
42 * |-------------| | | |
43 * | | | | |
44 * | line 3\0 |<---| | |
45 * | line 2\0 |<-----| |
46 * | line 1\0 |<-------|
47 * |-------------|
49 * The advantage of this method is that we optimize the buffer usage.
51 * The disadvantage is that the string pointers will be loaded in reverse
52 * order. We therefore sort the strings in reverse order as well, so we
53 * don't have to sort an already sorted buffer.
54 ****************************************************************************/
56 /***************************************************************************
57 * TODO: Implement a merge sort for files larger than the buffer
58 ****************************************************************************/
62 size_t buf_size;
63 static char *filename;
64 static int num_entries;
65 static char **pointers;
66 static char *stringbuffer;
67 static char crlf[2] = "\r\n";
68 static int bomsize;
70 /* Compare function for sorting backwards */
71 static int compare(const void* p1, const void* p2)
73 char *s1 = *(char **)p1;
74 char *s2 = *(char **)p2;
76 return rb->strcasecmp(s2, s1);
79 static void sort_buffer(void)
81 rb->qsort(pointers, num_entries, sizeof(char *), compare);
84 static int read_buffer(int offset)
86 int fd;
87 char *buf_ptr;
88 char *tmp_ptr;
89 int readsize;
91 fd = rb->open_utf8(filename, O_RDONLY);
92 if(fd < 0)
93 return 10 * fd - 1;
95 bomsize = rb->lseek(fd, 0, SEEK_CUR);
96 offset += bomsize;
98 /* Fill the buffer from the file */
99 rb->lseek(fd, offset, SEEK_SET);
100 readsize = rb->read(fd, stringbuffer, buf_size);
101 rb->close(fd);
103 if(readsize < 0)
104 return readsize * 10 - 2;
106 /* Temporary fix until we can do merged sorting */
107 if(readsize == (int)buf_size)
108 return buf_size; /* File too big */
110 buf_ptr = stringbuffer;
111 num_entries = 0;
113 do {
114 tmp_ptr = buf_ptr;
115 while(*buf_ptr != '\n' && buf_ptr < (char *)pointers) {
116 /* Terminate the string with CR... */
117 if(*buf_ptr == '\r')
118 *buf_ptr = 0;
119 buf_ptr++;
121 /* ...and with LF */
122 if(*buf_ptr == '\n')
123 *buf_ptr = 0;
124 else {
125 return tmp_ptr - stringbuffer; /* Buffer is full, return
126 the point to resume at */
129 pointers--;
130 *pointers = tmp_ptr;
131 num_entries++;
132 buf_ptr++;
133 } while(buf_ptr < stringbuffer + readsize);
135 return 0;
138 static int write_file(void)
140 char tmpfilename[MAX_PATH+1];
141 int fd;
142 int i;
143 int rc;
145 /* Create a temporary file */
146 rb->snprintf(tmpfilename, MAX_PATH+1, "%s.tmp", filename);
147 if (bomsize)
148 fd = rb->open_utf8(tmpfilename, O_WRONLY|O_CREAT|O_TRUNC);
149 else
150 fd = rb->open(tmpfilename, O_WRONLY|O_CREAT|O_TRUNC, 0666);
152 if(fd < 0)
153 return 10 * fd - 1;
155 /* Write the sorted strings, with appended CR/LF, to the temp file,
156 in reverse order */
157 for(i = num_entries-1;i >= 0;i--) {
158 rc = rb->write(fd, pointers[i], rb->strlen(pointers[i]));
159 if(rc < 0) {
160 rb->close(fd);
161 return 10 * rc - 2;
164 rc = rb->write(fd, crlf, 2);
165 if(rc < 0) {
166 rb->close(fd);
167 return 10 * rc - 3;
171 rb->close(fd);
173 /* Remove the original file */
174 rc = rb->remove(filename);
175 if(rc < 0) {
176 return 10 * rc - 4;
179 /* Replace the old file with the new */
180 rc = rb->rename(tmpfilename, filename);
181 if(rc < 0) {
182 return 10 * rc - 5;
184 return 0;
187 enum plugin_status plugin_start(const void* parameter)
189 char *buf;
190 int rc;
191 if(!parameter) return PLUGIN_ERROR;
193 filename = (char *)parameter;
195 buf = rb->plugin_get_audio_buffer(&buf_size); /* start munching memory */
197 stringbuffer = buf;
198 pointers = (char **)(buf + buf_size - sizeof(int));
200 rb->lcd_clear_display();
201 rb->splash(0, "Loading...");
203 rc = read_buffer(0);
204 if(rc == 0) {
205 rb->lcd_clear_display();
206 rb->splash(0, "Sorting...");
207 sort_buffer();
209 rb->lcd_clear_display();
210 rb->splash(0, "Writing...");
212 rc = write_file();
213 if(rc < 0) {
214 rb->lcd_clear_display();
215 rb->splashf(HZ, "Can't write file: %d", rc);
216 } else {
217 rb->lcd_clear_display();
218 rb->splash(HZ, "Done");
220 } else {
221 if(rc < 0) {
222 rb->lcd_clear_display();
223 rb->splashf(HZ, "Can't read file: %d", rc);
224 } else {
225 rb->lcd_clear_display();
226 rb->splash(HZ, "The file is too big");
230 return PLUGIN_OK;