src/client/xml_writer.c

   1 /* -*- mode: c; c-file-style: "openbsd" -*- */
   2 /*
   3  * Copyright (c) 2010 Andreas Hofmeister <andi@collax.com>
   4  *
   5  * Permission to use, copy, modify, and/or distribute this software for any
   6  * purpose with or without fee is hereby granted, provided that the above
   7  * copyright notice and this permission notice appear in all copies.
   8  *
   9  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
  10  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
  11  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
  12  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
  13  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
  14  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
  15  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  16  */
  17
  18 #include <stdio.h>
  19 #include <stdlib.h>
  20 #include <string.h>
  21
  22 #if defined(__clang__)
  23 #pragma clang diagnostic push
  24 #pragma clang diagnostic ignored "-Wdocumentation"
  25 #endif
  26 #include <libxml/encoding.h>
  27 #include <libxml/xmlwriter.h>
  28 #if defined(__clang__)
  29 #pragma clang diagnostic pop
  30 #endif
  31
  32 #include "writer.h"
  33 #include "../log.h"
  34
  35 struct xml_writer_private {
  36         FILE *fh;
  37         xmlTextWriterPtr xw;
  38         xmlDocPtr doc;
  39 };
  40
  41 void xml_start(struct writer *w , const char *tag, const char *descr ) {
  42         struct xml_writer_private *p = w->priv;
  43
  44         if (xmlTextWriterStartElement(p->xw, BAD_CAST tag) < 0)
  45                 log_warnx("lldpctl", "cannot start '%s' element", tag);
  46
  47         if (descr && (strlen(descr) > 0)) {
  48                 if (xmlTextWriterWriteFormatAttribute(p->xw, BAD_CAST "label", "%s", descr) < 0)
  49                         log_warnx("lldpctl", "cannot add attribute 'label' to element %s", tag);
  50         }
  51 }
  52
  53 void xml_attr(struct writer *w, const char *tag, const char *descr, const char *value ) {
  54         struct xml_writer_private *p = w->priv;
  55
  56         if (xmlTextWriterWriteFormatAttribute(p->xw, BAD_CAST tag, "%s", value?value:"") < 0)
  57                 log_warnx("lldpctl", "cannot add attribute %s with value %s", tag, value?value:"(none)");
  58 }
  59
  60 void xml_data(struct writer *w, const char *data) {
  61         struct xml_writer_private *p = w->priv;
  62         if (xmlTextWriterWriteString(p->xw, BAD_CAST (data?data:"")) < 0 )
  63                 log_warnx("lldpctl", "cannot add '%s' as data to element", data?data:"(none)");
  64 }
  65
  66 void xml_end(struct writer *w) {
  67         struct xml_writer_private *p = w->priv;
  68
  69         if (xmlTextWriterEndElement(p->xw) < 0 )
  70                 log_warnx("lldpctl", "cannot end element");
  71 }
  72
  73 #define MY_ENCODING "UTF-8"
  74
  75 void xml_finish(struct writer *w) {
  76         struct xml_writer_private *p = w->priv;
  77         int failed = 0;
  78
  79         if (xmlTextWriterEndDocument(p->xw) < 0 ) {
  80                 log_warnx("lldpctl", "cannot finish document");
  81                 failed = 1;
  82         }
  83
  84         xmlFreeTextWriter(p->xw);
  85
  86         if (!failed)
  87                 xmlDocDump(p->fh, p->doc);
  88
  89         xmlFreeDoc(p->doc);
  90
  91         free(w->priv);
  92         free(w);
  93 }
  94
  95 struct writer *xml_init(FILE *fh) {
  96
  97         struct writer *result;
  98         struct xml_writer_private *priv;
  99
 100         priv = malloc(sizeof(*priv));
 101         priv->fh = fh;
 102         if (!priv) {
 103                 fatalx("lldpctl", "out of memory");
 104                 return NULL;
 105         }
 106
 107         priv->xw = xmlNewTextWriterDoc(&(priv->doc), 0);
 108         if (!priv->xw) {
 109                 fatalx("lldpctl", "cannot create xml writer");
 110                 return NULL;
 111         }
 112
 113         xmlTextWriterSetIndent(priv->xw, 4);
 114
 115         if (xmlTextWriterStartDocument(priv->xw, NULL, MY_ENCODING, NULL) < 0 ) {
 116                 fatalx("lldpctl", "cannot start xml document");
 117                 return NULL;
 118         }
 119
 120         result = malloc(sizeof(struct writer));
 121         if (!result) {
 122                 fatalx("lldpctl", "out of memory");
 123                 return NULL;
 124         }
 125
 126         result->priv  = priv;
 127         result->start = xml_start;
 128         result->attr  = xml_attr;
 129         result->data  = xml_data;
 130         result->end   = xml_end;
 131         result->finish= xml_finish;
 132
 133         return result;
 134 }