Work on logformat

git-svn-id: file:///svn/tokudb@708 c7de825b-a66e-492c-adef-691d508d4ae1

newbrt/logformat.c

+/* This file defines the logformat in an executable fashion.
+ * This code is used to generate
+ *   The code that writes into the log.
+ *   The code that reads the log and prints it to stdout (the log_print utility)
+ *   The code that reads the log for recovery.
+ *   The struct definitions.
+ *   The Latex documentation.
+ */
+#include <stdio.h>
+#include <assert.h>
+
+typedef struct field {
+    char *type;
+    char *name;
+} F;
+
+#define NULLFIELD {0,0}
+#define FA (F[])
+
+struct logtype {
+    char *name;
+    char command;
+    struct field *fields;
+};
+
+// In the fields, don't mention the command, the LSN, the CRC or the trailing LEN.
+
+const struct logtype logtypes[] = {
+    {"delete", 'D', FA{{"FILENUM", "filenum"},
+		       {"DISKOFF", "diskoff"},
+		       {"BYTESTRING", "key"},
+		       {"BYTESTRING", "data"},
+		       NULLFIELD}},
+    {"commit", 'C', FA{{"TXNID", "txnid"},NULLFIELD}},
+    {0,0,FA{NULLFIELD}}
+};
+    
+#define DO_LOGTYPES(lt, body) ({ \
+    const struct logtype *lt;    \
+    for (lt=&logtypes[0]; lt->name; lt++) { \
+	body; \
+    } })
+
+#define DO_FIELDS(fld, lt, body) ({ \
+    struct field *fld; \
+    for (fld=lt->fields; fld->type; fld++) { \
+        body; \
+    } })
+
+void generate_log_struct(void) {
+    FILE *f = fopen("log_struct.h", "w");
+    assert(f!=0);
+    DO_LOGTYPES(lt,
+		({  fprintf(f, "struct logtype_%s {\n", lt->name);
+		    fprintf(f, "  %-16s lsn;\n", "LSN");
+		    DO_FIELDS(ft, lt,
+			      fprintf(f, "  %-16s %s;\n", ft->type, ft->name));
+		    fprintf(f, "  %-16s crc;\n", "u_int_32");
+		    fprintf(f, "  %-16s len;\n", "u_int_32");
+		    fprintf(f, "};\n");
+		}));
+    int r=fclose(f);
+    assert(r==0);
+}
+
+void generate_log_writer(void) {
+    FILE *f = fopen("log_write.c", "w");
+    assert(f!=0);
+    DO_LOGTYPES(lt, ({
+			fprintf(f, "int toku_log_%s (TOKULOGGE logger, LSN lsn", lt->name);
+			DO_FIELDS(ft, lt,
+				  fprintf(f, ", %s %s", ft->type, ft->name));
+			fprintf(f, ") {\n");
+			fprintf(f, "  const int buflen= (1 // log command\n");
+			fprintf(f, "                     +8 // lsn\n");
+			DO_FIELDS(ft, lt,
+				  fprintf(f, "                     +toku_logsizeof_%s(%s)\n", ft->type, ft->name));
+			fprintf(f, "                     +8 // crc + len\n");
+			fprintf(f, "                     );\n");
+			fprintf(f, "  struct wbuf wbuf;\n");
+			fprintf(f, "  const char *buf = toku_malloc(buflen);\n");
+			fprintf(f, "  if (buf==0) return errno;\n");
+			fprintf(f, "  wbuf_init(&wbuf, buf, buflen)\n");
+			fprintf(f, "  wbuf_char(&wbuf, '%c');\n", lt->command);
+			fprintf(f, "  wbuf_lsn(&wbuf, lsn);\n");
+			DO_FIELDS(ft, lt,
+				  fprintf(f, "  wbuf_%s(&wbuf, %s);\n", ft->type, ft->name));
+			fprintf(f, "  int r= tokulogger_finish(logger, &wbuf);\n");
+			fprintf(f, "  assert(buf.ndone==buflen);\n");
+			fprintf(f, "  toku_free(buf);\n");
+			if (lt->command=='C') {
+			    fprintf(f, "  if (r!=0) return r;\n");
+			    fprintf(f, "  // commit has some extra work to do.\n");
+			    fprintf(f, "  if (txn->parent) return 0; // don't fsync if there is a parent.\n");
+			    fprintf(f, "  else return tokulogger_fsync(logger);\n");
+			} else {
+			    fprintf(f, "  return r;\n");
+			}
+			fprintf(f, "}\n\n");
+		    }));
+
+    int r=fclose(f);
+    assert(r==0);
+}
+
+
+int main (int argc __attribute__((__unused__)), char *argv[]  __attribute__((__unused__))) {
+    generate_log_struct();
+    generate_log_writer();
+    return 0;
+}
+