git.gag.com Git - debian/amanda/blob - server-src/taper-port-source.c

   1 /*
   2  * Amanda, The Advanced Maryland Automatic Network Disk Archiver
   3  * Copyright (c) 2005-2008 Zmanda Inc.
   4  *
   5  * This library is free software; you can redistribute it and/or
   6  * modify it under the terms of the GNU Lesser General Public
   7  * License as published by the Free Software Foundation; either
   8  * version 2.1 of the License, or (at your option) any later version.
   9  *
  10  * This library is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13  * Lesser General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU Lesser General Public
  16  * License along with this library; if not, write to the Free Software
  17  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
  18  */
  19
  20 #define selfp (self->_priv)
  21
  22 #include "taper-port-source.h"
  23
  24 /* here are local prototypes */
  25 static void taper_port_source_class_init (TaperPortSourceClass * c);
  26 static ssize_t taper_port_source_read (TaperSource * pself, void * buf,
  27                                        size_t count);
  28 static void taper_port_source_init (TaperPortSource * self);
  29 static gboolean taper_port_source_is_partial(TaperSource * self);
  30 static int taper_port_source_predict_parts(TaperSource * pself);
  31 static dumpfile_t * taper_port_source_get_first_header(TaperSource * pself);
  32
  33
  34 /* pointer to the class of our parent */
  35 static TaperSourceClass *parent_class = NULL;
  36
  37 GType
  38 taper_port_source_get_type (void)
  39 {
  40     static GType type = 0;
  41
  42     if G_UNLIKELY(type == 0) {
  43         static const GTypeInfo info = {
  44             sizeof (TaperPortSourceClass),
  45             (GBaseInitFunc) NULL,
  46             (GBaseFinalizeFunc) NULL,
  47             (GClassInitFunc) taper_port_source_class_init,
  48             (GClassFinalizeFunc) NULL,
  49             NULL /* class_data */,
  50             sizeof (TaperPortSource),
  51             0 /* n_preallocs */,
  52             (GInstanceInitFunc) taper_port_source_init,
  53             NULL
  54         };
  55
  56         type = g_type_register_static (TAPER_SOURCE_TYPE, "TaperPortSource",
  57                                        &info, (GTypeFlags)0);
  58     }
  59
  60     return type;
  61 }
  62
  63 static void taper_port_source_finalize(GObject * obj_self) {
  64     TaperPortSource *self = TAPER_PORT_SOURCE(obj_self);
  65     if (self->socket_fd >= 0) {
  66         aclose(self->socket_fd);
  67     }
  68
  69     G_OBJECT_CLASS (parent_class)->finalize (obj_self);
  70 }
  71
  72 static void taper_port_source_class_init (TaperPortSourceClass * c) {
  73     TaperSourceClass *taper_source_class = (TaperSourceClass *)c;
  74     GObjectClass *g_object_class = (GObjectClass*)c;
  75
  76     parent_class = g_type_class_ref (TAPER_SOURCE_TYPE);
  77
  78     taper_source_class->read = taper_port_source_read;
  79     taper_source_class->is_partial = taper_port_source_is_partial;
  80     taper_source_class->get_first_header = taper_port_source_get_first_header;
  81     taper_source_class->predict_parts = taper_port_source_predict_parts;
  82
  83     g_object_class->finalize = taper_port_source_finalize;
  84 }
  85
  86 /* Check if the header has been read; if not, read and parse it. */
  87 static void check_first_header(TaperPortSource * self) {
  88     TaperSource * pself = (TaperSource*)self;
  89     char buf[DISK_BLOCK_BYTES];
  90     size_t result;
  91     dumpfile_t * rval;
  92
  93     if (G_LIKELY(pself->first_header != NULL)) {
  94         return;
  95     }
  96
  97     result = full_read(self->socket_fd, buf, DISK_BLOCK_BYTES);
  98     if (result != DISK_BLOCK_BYTES) {
  99         return;
 100     }
 101     rval = malloc(sizeof(dumpfile_t));
 102     parse_file_header(buf, rval, DISK_BLOCK_BYTES);
 103     pself->first_header = rval;
 104 }
 105
 106 static int taper_port_source_predict_parts(TaperSource * pself) {
 107     TaperPortSource * self = TAPER_PORT_SOURCE(pself);
 108     g_return_val_if_fail(self != NULL, -1);
 109
 110     return 1;
 111 }
 112
 113 static dumpfile_t * taper_port_source_get_first_header(TaperSource * pself) {
 114     TaperPortSource * self = TAPER_PORT_SOURCE(pself);
 115     g_return_val_if_fail(self != NULL, NULL);
 116
 117     check_first_header(self);
 118
 119     if (parent_class->get_first_header) {
 120         return (parent_class->get_first_header)(pself);
 121     } else {
 122         return NULL;
 123     }
 124 }
 125
 126 static void taper_port_source_init (TaperPortSource * self) {
 127     /* Subclasses may do as they please, but if we are the final word,
 128        then there will be no rewinding. */
 129     if (G_TYPE_FROM_INSTANCE(self) == TAPER_TYPE_PORT_SOURCE) {
 130         TAPER_SOURCE(self)->max_part_size = 0;
 131     }
 132     self->socket_fd = -1;
 133 }
 134
 135 static ssize_t taper_port_source_read (TaperSource * pself, void * buf,
 136                                        size_t count) {
 137     TaperPortSource * self = (TaperPortSource*)pself;
 138     int read_result;
 139     g_return_val_if_fail (self != NULL, -1);
 140     g_return_val_if_fail (TAPER_IS_PORT_SOURCE (pself), -1);
 141     g_return_val_if_fail (buf != NULL, -1);
 142     g_return_val_if_fail (count > 0, -1);
 143
 144     check_first_header(self);
 145
 146     for (;;) {
 147         read_result = read(self->socket_fd, buf, count);
 148         if (read_result > 0) {
 149             return read_result;
 150         } else if (read_result == 0) {
 151             pself->end_of_data = TRUE;
 152             aclose(self->socket_fd);
 153             return 0;
 154         } else if (0
 155 #ifdef EAGAIN
 156                    || errno == EAGAIN
 157 #endif
 158 #ifdef EWOULDBLOCK
 159                    || errno == EWOULDBLOCK
 160 #endif
 161 #ifdef EINTR
 162                    || errno == EINTR
 163 #endif
 164                    ) {
 165             /* Try again. */
 166             continue;
 167         } else {
 168             /* Error occured. */
 169             return read_result;
 170         }
 171     }
 172
 173     g_assert_not_reached();
 174 }
 175
 176 static gboolean
 177 taper_port_source_is_partial(TaperSource * pself) {
 178     struct cmdargs *cmdargs;
 179     gboolean result;
 180     TaperPortSource * self = (TaperPortSource*)pself;
 181
 182     if (self->socket_fd >= 0)
 183         return FALSE;
 184
 185     /* Query DRIVER about partial dump. */
 186     putresult(DUMPER_STATUS, "%s\n", pself->driver_handle);
 187     cmdargs = getcmd();
 188     if (cmdargs->cmd == FAILED) {
 189         result = TRUE;
 190     } else if (cmdargs->cmd == DONE) {
 191         result = FALSE;
 192     } else {
 193         error("Driver gave invalid response "
 194               "to query DUMPER-STATUS.\n");
 195         g_assert_not_reached();
 196     }
 197
 198     free_cmdargs(cmdargs);
 199     return result;
 200 }