Gene Selkov's SEG datatype (GiST example code)

1 files changed, 79 insertions, 0 deletions

diff --git a/contrib/seg/buffer.c b/contrib/seg/buffer.c
new file mode 100644
index 00000000000..f4dfc1edcd3
--- /dev/null
+++ b/contrib/seg/buffer.c
@@ -0,0 +1,79 @@
+/* This module defines the parse buffer and routines for setting/reading it */
+
+#include "postgres.h"
+
+#include "utils/elog.h"
+
+static char *       PARSE_BUFFER;
+static char *       PARSE_BUFFER_PTR; 
+static unsigned int PARSE_BUFFER_SIZE; 
+static unsigned int SCANNER_POS;
+
+void         set_parse_buffer( char* s );
+void         reset_parse_buffer( void );
+int          read_parse_buffer( void );
+char *       parse_buffer( void );
+char *       parse_buffer_ptr( void );
+unsigned int parse_buffer_curr_char( void );
+unsigned int parse_buffer_size( void );
+unsigned int parse_buffer_pos( void );
+
+extern void seg_flush_scanner_buffer(void); /* defined in segscan.l */
+
+void set_parse_buffer( char* s )
+{
+  PARSE_BUFFER = s;
+  PARSE_BUFFER_SIZE = strlen(s);
+  if ( PARSE_BUFFER_SIZE == 0 ) {
+    elog(ERROR, "seg_in: can't parse an empty string");
+  }
+  PARSE_BUFFER_PTR = PARSE_BUFFER;
+  SCANNER_POS = 0;
+}
+
+void reset_parse_buffer( void )
+{
+  PARSE_BUFFER_PTR = PARSE_BUFFER;
+  SCANNER_POS = 0;
+  seg_flush_scanner_buffer();
+}
+
+int read_parse_buffer( void )
+{
+  int c;
+  /*
+  c = *PARSE_BUFFER_PTR++;
+  SCANNER_POS++;
+  */
+  c = PARSE_BUFFER[SCANNER_POS];
+  if(SCANNER_POS < PARSE_BUFFER_SIZE)
+    SCANNER_POS++;
+  return c;
+}
+
+char * parse_buffer( void )
+{
+  return PARSE_BUFFER;
+}
+
+unsigned int parse_buffer_curr_char( void )
+{
+  return PARSE_BUFFER[SCANNER_POS];
+}
+
+char * parse_buffer_ptr( void )
+{
+  return PARSE_BUFFER_PTR;
+}
+
+unsigned int parse_buffer_pos( void )
+{
+  return SCANNER_POS;
+}
+
+unsigned int parse_buffer_size( void )
+{
+  return PARSE_BUFFER_SIZE;
+}
+
+