file_write.c

   1 /*
   2  * Copyright (C) 2006-2009 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         /** non-zero if \a fd was added to the write fd set */
  32         int check_fd;
  33 };
  34
  35 /*
  36  * Get a random filename.
  37  *
  38  * This is by no means a secure way to create temporary files in a hostile
  39  * directory like \p /tmp. However, we use it only for creating temp files in
  40  * ~/.paraslash, for which it is OK. Result must be freed by the caller.
  41  */
  42 __must_check __malloc static char *random_filename(void)
  43 {
  44         char *result, *home = para_homedir();
  45         struct timeval tv;
  46
  47         gettimeofday(&tv, NULL);
  48         srandom(tv.tv_usec);
  49         result = make_message("%s/.paraslash/%08lu", home,
  50                 para_random(99999999));
  51         free(home);
  52         return result;
  53 }
  54
  55 static int file_write_open(struct writer_node *wn)
  56 {
  57         struct private_file_write_data *pfwd = para_calloc(
  58                 sizeof(struct private_file_write_data));
  59         struct file_write_args_info *conf = wn->conf;
  60         char *filename;
  61
  62         if (conf->filename_given)
  63                 filename = conf->filename_arg;
  64         else
  65                 filename = random_filename();
  66         wn->private_data = pfwd;
  67         pfwd->fd = open(filename, O_WRONLY | O_CREAT, S_IRUSR | S_IWUSR);
  68         if (!conf->filename_given)
  69                 free(filename);
  70         if (pfwd->fd >= 0)
  71                 return 1;
  72         free(pfwd);
  73         return -E_FW_OPEN;
  74 }
  75
  76 static void file_write_pre_select_btr(struct sched *s, struct task *t)
  77 {
  78         struct writer_node *wn = container_of(t, struct writer_node, task);
  79         struct private_file_write_data *pfwd = wn->private_data;
  80         int ret;
  81
  82         t->error = 0;
  83         pfwd->check_fd = 0;
  84         ret = btr_node_status(wn->btrn, wn->min_iqs, BTR_NT_LEAF);
  85         if (ret > 0) {
  86                 para_fd_set(pfwd->fd, &s->wfds, &s->max_fileno);
  87                 pfwd->check_fd = 1;
  88         } else if (ret < 0) {
  89                 s->timeout.tv_sec = 0;
  90                 s->timeout.tv_usec = 1;
  91         }
  92 }
  93
  94 static void file_write_close(struct writer_node *wn)
  95 {
  96         struct private_file_write_data *pfwd = wn->private_data;
  97
  98         close(pfwd->fd);
  99         free(pfwd);
 100 }
 101
 102 static void file_write_post_select_btr(__a_unused struct sched *s,
 103                 struct task *t)
 104 {
 105         struct writer_node *wn = container_of(t, struct writer_node, task);
 106         struct private_file_write_data *pfwd = wn->private_data;
 107         struct btr_node *btrn = wn->btrn;
 108         int ret;
 109         char *buf;
 110         size_t bytes;
 111
 112         t->error = 0;
 113         ret = btr_node_status(btrn, wn->min_iqs, BTR_NT_LEAF);
 114         if (ret == 0)
 115                 return;
 116         if (ret < 0)
 117                 goto err;
 118         if (!pfwd->check_fd)
 119                 return;
 120         if (!FD_ISSET(pfwd->fd, &s->wfds))
 121                 return;
 122         bytes = btr_next_buffer(btrn, &buf);
 123         assert(bytes > 0);
 124         //PARA_INFO_LOG("writing %zu\n", bytes);
 125         ret = write(pfwd->fd, buf, bytes);
 126         if (ret < 0)
 127                 goto err;
 128         btr_consume(btrn, ret);
 129         return;
 130 err:
 131         assert(ret < 0);
 132         t->error = ret;
 133         btr_remove_node(btrn);
 134 }
 135
 136 __malloc static void *file_write_parse_config(const char *options)
 137 {
 138         struct file_write_args_info *conf
 139                 = para_calloc(sizeof(struct file_write_args_info));
 140         int ret = file_cmdline_parser_string(options, conf, "file_write");
 141
 142         PARA_INFO_LOG("conf->filename_given: %d\n", conf->filename_given);
 143         if (!ret)
 144                 return conf;
 145         free(conf);
 146         return NULL;
 147 }
 148
 149 static void file_write_free_config(void *conf)
 150 {
 151         file_cmdline_parser_free(conf);
 152 }
 153
 154 /** the init function of the file writer */
 155 void file_write_init(struct writer *w)
 156 {
 157         struct file_write_args_info dummy;
 158
 159         file_cmdline_parser_init(&dummy);
 160         w->open = file_write_open;
 161         w->pre_select_btr = file_write_pre_select_btr;
 162         w->post_select_btr = file_write_post_select_btr;
 163         w->parse_config = file_write_parse_config;
 164         w->free_config = file_write_free_config;
 165         w->close = file_write_close;
 166         w->shutdown = NULL; /* nothing to do */
 167         w->help = (struct ggo_help) {
 168                 .short_help = file_write_args_info_help,
 169                 .detailed_help = file_write_args_info_detailed_help
 170         };
 171         file_cmdline_parser_free(&dummy);
 172 }