1 files changed, 292 insertions, 0 deletions

diff --git a/src/plugins/man_extractor.c b/src/plugins/man_extractor.c
new file mode 100644
index 0000000..f074e5b
--- /dev/null
+++ b/src/plugins/man_extractor.c
@@ -0,0 +1,292 @@
+/*
+     This file is part of libextractor.
+     (C) 2002, 2003, 2004, 2009, 2012 Vidyut Samanta and Christian Grothoff
+
+     libextractor is free software; you can redistribute it and/or modify
+     it under the terms of the GNU General Public License as published
+     by the Free Software Foundation; either version 3, or (at your
+     option) any later version.
+
+     libextractor is distributed in the hope that it will be useful, but
+     WITHOUT ANY WARRANTY; without even the implied warranty of
+     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+     General Public License for more details.
+
+     You should have received a copy of the GNU General Public License
+     along with libextractor; see the file COPYING.  If not, write to the
+     Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+     Boston, MA 02111-1307, USA.
+ */
+/**
+ * @file plugins/man_extractor.c
+ * @brief plugin to support man pages
+ * @author Christian Grothoff
+ */
+#include "platform.h"
+#include "extractor.h"
+#include <ctype.h>
+
+
+/**
+ * Create string from first 'n' characters of 'str'.  See 'strndup'.
+ *
+ * @param str input string
+ * @param n desired output length (plus 0-termination)
+ * @return copy of first 'n' bytes from 'str' plus 0-terminator, NULL on error
+ */
+static char *
+stndup (const char *str, size_t n)
+{
+  char *tmp;
+
+  if (NULL == (tmp = malloc (n + 1)))
+    return NULL;
+  tmp[n] = '\0';
+  memcpy (tmp, str, n);
+  return tmp;
+}
+
+
+/**
+ * Give a metadata item to LE.  Removes double-quotes and
+ * makes sure we don't pass empty strings or NULL pointers.
+ *
+ * @param type metadata type to use
+ * @param keyword metdata value; freed in the process
+ * @param proc function to call with meta data
+ * @param proc_cls closure for 'proc'
+ * @return 0 to continue extracting, 1 if we are done
+ */
+static int
+add_keyword (enum EXTRACTOR_MetaType type,
+             char *keyword, 
+             EXTRACTOR_MetaDataProcessor proc,
+             void *proc_cls)
+{
+  int ret;
+  char *value;
+  
+  if (NULL == keyword)
+    return 0;
+  if ( (keyword[0] == '\"') && 
+       (keyword[strlen (keyword) - 1] == '\"') )
+    {
+      keyword[strlen (keyword) - 1] = '\0';
+      value = &keyword[1];
+    }
+  else
+    value = keyword;
+  if (0 == strlen (value))
+    {
+      free (keyword);
+      return 0;
+    }
+  ret = proc (proc_cls, 
+              "man",
+              type,
+              EXTRACTOR_METAFORMAT_UTF8,
+              "text/plain",
+              value,
+              strlen (value)+1);
+  free (keyword);
+  return ret;
+}
+
+
+/**
+ * Find the end of the current token (which may be quoted).
+ *
+ * @param end beginning of the current token, updated to its end; set to size + 1 if the token does not end properly
+ * @param buf input buffer with the characters
+ * @param size number of bytes in buf
+ */
+static void
+find_end_of_token (size_t *end,
+                   const char *buf, 
+                   const size_t size)
+{
+  int quot;
+
+  quot = 0;
+  while ( (*end < size) &&
+          ( (0 != (quot & 1)) ||
+            ((' ' != buf[*end])) ) )
+    {
+      if ('\"' == buf[*end])
+        quot++;
+      (*end)++;
+    }
+  if (1 == (quot & 1))
+    (*end) = size + 1;
+}
+
+
+/**
+ * How many bytes do we actually try to scan? (from the beginning
+ * of the file).
+ */
+#define MAX_READ (16 * 1024)
+
+
+/**
+ * Add a keyword to LE.
+ * 
+ * @param t type to use
+ * @param s keyword to give to LE
+ */
+#define ADD(t,s) do { if (0 != add_keyword (t, s, ec->proc, ec->cls)) return; } while (0)
+
+
+/**
+ * Main entry method for the man page extraction plugin.  
+ *
+ * @param ec extraction context provided to the plugin
+ */
+void
+EXTRACTOR_man_extract_method (struct EXTRACTOR_ExtractContext *ec)
+{
+  const size_t xlen = strlen (".TH ");
+  size_t pos;
+  size_t xsize;
+  size_t end;
+  void *data;
+  ssize_t size;
+  char *buf;
+  
+  if (0 >= (size = ec->read (ec->cls, &data, MAX_READ)))
+    return;
+  buf = data;
+  pos = 0;
+  if (size < xlen)
+    return;
+  /* find actual beginning of the man page (.TH);
+     abort if we find non-printable characters */
+  while ( (pos < size - xlen) &&
+          ( (0 != strncmp (".TH ",
+                           &buf[pos],
+                           xlen)) || 
+            ( (0 != pos) && 
+              (buf[pos - 1] != '\n') ) ) )
+    {
+      if ( (! isgraph ((unsigned char) buf[pos])) && 
+           (! isspace ((unsigned char) buf[pos])) )
+        return;
+      pos++;
+    }
+  if (0 != strncmp (".TH ", &buf[pos], xlen))
+    return;
+
+  /* find end of ".TH"-line */
+  xsize = pos;
+  while ( (xsize < size) && ('\n' != buf[xsize]) )
+    xsize++;
+  /* limit processing to ".TH" line */
+  size = xsize;
+
+  /* skip over ".TH" */
+  pos += xlen;
+
+  /* first token is the title */
+  end = pos;
+  find_end_of_token (&end, buf, size);
+  if (end > size)
+    return;
+  if (end > pos)
+    {
+      ADD (EXTRACTOR_METATYPE_TITLE, stndup (&buf[pos], end - pos));
+      pos = end + 1;
+    }
+  if (pos >= size)
+    return;
+  
+  /* next token is the section */
+  end = pos;
+  find_end_of_token (&end, buf, size);
+  if (end > size)
+    return;
+  if ('\"' == buf[pos])
+    pos++;
+  if ((end - pos >= 1) && (end - pos <= 4))
+    {
+      switch (buf[pos])
+        {
+        case '1':
+          ADD (EXTRACTOR_METATYPE_SECTION,
+               strdup (_("Commands")));
+          break;
+        case '2':
+          ADD (EXTRACTOR_METATYPE_SECTION,
+               strdup (_("System calls")));
+          break;
+        case '3':
+          ADD (EXTRACTOR_METATYPE_SECTION,
+               strdup (_("Library calls")));
+          break;
+        case '4':
+          ADD (EXTRACTOR_METATYPE_SECTION,
+               strdup (_("Special files")));
+          break;
+        case '5':
+          ADD (EXTRACTOR_METATYPE_SECTION,
+               strdup (_("File formats and conventions")));
+          break;
+        case '6':
+          ADD (EXTRACTOR_METATYPE_SECTION,
+               strdup (_("Games")));
+          break;
+        case '7':
+          ADD (EXTRACTOR_METATYPE_SECTION,
+               strdup (_("Conventions and miscellaneous")));
+          break;
+        case '8':
+          ADD (EXTRACTOR_METATYPE_SECTION,
+               strdup (_("System management commands")));
+          break;
+        case '9':
+          ADD (EXTRACTOR_METATYPE_SECTION,
+               strdup (_("Kernel routines")));
+          break;
+        default:
+          ADD (EXTRACTOR_METATYPE_SECTION,
+               stndup (&buf[pos], 1));
+        }
+      pos = end + 1;
+    }
+  end = pos;
+
+  /* next token is the modification date */
+  find_end_of_token (&end, buf, size);
+  if (end > size)
+    return;  
+  if (end > pos)
+    {
+      ADD (EXTRACTOR_METATYPE_MODIFICATION_DATE, stndup (&buf[pos], end - pos));
+      pos = end + 1;
+    }
+
+  /* next token is the source of the man page */
+  end = pos;
+  find_end_of_token (&end, buf, size);
+  if (end > size)
+    return;
+  if (end > pos)
+    {
+      ADD (EXTRACTOR_METATYPE_SOURCE,
+           stndup (&buf[pos], end - pos));
+      pos = end + 1;
+    }
+
+  /* last token is the title of the book the man page belongs to */
+  end = pos;
+  find_end_of_token (&end, buf, size);
+  if (end > size)
+    return;
+  if (end > pos)
+    {
+      ADD (EXTRACTOR_METATYPE_BOOK_TITLE,
+           stndup (&buf[pos], end - pos));
+      pos = end + 1;
+    }
+}
+
+/* end of man_extractor.c */