7497dfaa0f00e6be8c8856a2659bcaaa65938100
[paraslash.git] / file_write.c
1 /*
2 * Copyright (C) 2006-2010 Andre Noll <maan@systemlinux.org>
3 *
4 * Licensed under the GPL v2. For licencing details see COPYING.
5 */
6
7 /** \file file_write.c simple output plugin for testing purposes */
8
9 #include <regex.h>
10 #include <sys/types.h>
11 #include <dirent.h>
12 #include <sys/time.h>
13 #include <stdbool.h>
14
15 #include "para.h"
16 #include "list.h"
17 #include "sched.h"
18 #include "ggo.h"
19 #include "buffer_tree.h"
20 #include "write.h"
21 #include "write_common.h"
22 #include "string.h"
23 #include "fd.h"
24 #include "file_write.cmdline.h"
25 #include "error.h"
26
27 /** Data specific to the file writer. */
28 struct private_file_write_data {
29 /** The file descriptor of the output file. */
30 int fd;
31 };
32
33 /*
34 * Get a random filename.
35 *
36 * This is by no means a secure way to create temporary files in a hostile
37 * directory like \p /tmp. However, we use it only for creating temp files in
38 * ~/.paraslash, for which it is OK. Result must be freed by the caller.
39 */
40 __must_check __malloc static char *random_filename(void)
41 {
42 char *result, *home = para_homedir();
43 struct timeval tv;
44
45 gettimeofday(&tv, NULL);
46 srandom(tv.tv_usec);
47 result = make_message("%s/.paraslash/%08lu", home,
48 para_random(99999999));
49 free(home);
50 return result;
51 }
52
53 static int file_write_open(struct writer_node *wn)
54 {
55 struct private_file_write_data *pfwd = para_calloc(sizeof(*pfwd));
56
57 wn->private_data = pfwd;
58 pfwd->fd = -1;
59 return 0;
60 }
61
62 static int prepare_output_file(struct writer_node *wn)
63 {
64 struct file_write_args_info *conf = wn->conf;
65 struct private_file_write_data *pfwd = wn->private_data;
66 char *filename;
67 int ret;
68
69 if (conf->filename_given)
70 filename = conf->filename_arg;
71 else
72 filename = random_filename();
73 ret = para_open(filename, O_WRONLY | O_CREAT, S_IRUSR | S_IWUSR);
74 if (!conf->filename_given)
75 free(filename);
76 if (ret < 0)
77 goto out;
78 pfwd->fd = ret;
79 ret = mark_fd_blocking(pfwd->fd);
80 if (ret >= 0)
81 return 1;
82 close(pfwd->fd);
83 out:
84 free(pfwd);
85 return ret;
86 }
87
88 static void file_write_pre_select(struct sched *s, struct task *t)
89 {
90 struct writer_node *wn = container_of(t, struct writer_node, task);
91 struct private_file_write_data *pfwd = wn->private_data;
92 int ret;
93
94 t->error = 0;
95 ret = btr_node_status(wn->btrn, wn->min_iqs, BTR_NT_LEAF);
96 if (ret > 0 && pfwd->fd >= 0)
97 para_fd_set(pfwd->fd, &s->wfds, &s->max_fileno);
98 else if (ret != 0) /* error or bos and fd not yet open */
99 sched_min_delay(s);
100 }
101
102 static void file_write_close(struct writer_node *wn)
103 {
104 struct private_file_write_data *pfwd = wn->private_data;
105
106 if (pfwd->fd >= 0)
107 close(pfwd->fd);
108 free(pfwd);
109 }
110
111 static void file_write_post_select(__a_unused struct sched *s,
112 struct task *t)
113 {
114 struct writer_node *wn = container_of(t, struct writer_node, task);
115 struct private_file_write_data *pfwd = wn->private_data;
116 struct btr_node *btrn = wn->btrn;
117 int ret;
118 char *buf;
119 size_t bytes;
120
121 t->error = 0;
122 ret = btr_node_status(btrn, wn->min_iqs, BTR_NT_LEAF);
123 if (ret <= 0)
124 goto out;
125 if (pfwd->fd < 0) {
126 ret = prepare_output_file(wn);
127 if (ret < 0)
128 goto out;
129 }
130 if (!FD_ISSET(pfwd->fd, &s->wfds))
131 return;
132 bytes = btr_next_buffer(btrn, &buf);
133 assert(bytes > 0);
134 //PARA_INFO_LOG("writing %zu\n", bytes);
135 ret = write(pfwd->fd, buf, bytes);
136 if (ret < 0)
137 goto out;
138 btr_consume(btrn, ret);
139 out:
140 if (ret < 0)
141 btr_remove_node(btrn);
142 t->error = ret;
143 }
144
145 __malloc static void *file_write_parse_config_or_die(const char *options)
146 {
147 struct file_write_args_info *conf = para_calloc(sizeof(*conf));
148
149 /* exits on errors */
150 file_cmdline_parser_string(options, conf, "file_write");
151 return conf;
152 }
153
154 static void file_write_free_config(void *conf)
155 {
156 file_cmdline_parser_free(conf);
157 }
158
159 /** the init function of the file writer */
160 void file_write_init(struct writer *w)
161 {
162 struct file_write_args_info dummy;
163
164 file_cmdline_parser_init(&dummy);
165 w->open = file_write_open;
166 w->pre_select = file_write_pre_select;
167 w->post_select = file_write_post_select;
168 w->parse_config_or_die = file_write_parse_config_or_die;
169 w->free_config = file_write_free_config;
170 w->close = file_write_close;
171 w->shutdown = NULL; /* nothing to do */
172 w->help = (struct ggo_help) {
173 .short_help = file_write_args_info_help,
174 .detailed_help = file_write_args_info_detailed_help
175 };
176 file_cmdline_parser_free(&dummy);
177 }