[sql] add a collator for log level

Fix for #77

src/collation-functions.cc

@@ -29,6 +29,8 @@
  * @file logfile_sub_source.hh
  */
 
+#include "config.h"
+
 #include <stdio.h>
 #include <string.h>
 #include <sqlite3.h>
@@ -39,6 +41,8 @@
 
 #include <algorithm>
 
+#include "log_format.hh"
+
 extern "C" {
         #include "strnatcmp.h"
 }
@@ -153,6 +157,15 @@ int sql_strnatcasecmp(void *ptr,
     return strnatcasecmp(a_len, (char *)a_in, b_len, (char *)b_in);
 }
 
+static
+int sql_loglevelcmp(void *ptr,
+    int a_len, const void *a_in,
+    int b_len, const void *b_in)
+{
+    return logline::levelcmp((const char *)a_in, a_len,
+        (const char *)b_in, b_len);
+}
+
 int register_collation_functions(sqlite3 *db)
 {
     sqlite3_create_collation(db, "ipaddress", SQLITE_UTF8, NULL, ipaddress);
@@ -160,6 +173,8 @@ int register_collation_functions(sqlite3 *db)
                              sql_strnatcmp);
     sqlite3_create_collation(db, "naturalnocase", SQLITE_UTF8, NULL,
                              sql_strnatcasecmp);
+    sqlite3_create_collation(db, "loglevel", SQLITE_UTF8, NULL,
+                             sql_loglevelcmp);
 
     return 0;
 }

src/log_format.cc

@@ -123,6 +123,41 @@ logline::level_t logline::string2level(const char *levelstr, size_t len, bool ex
     return retval;
 }
 
+logline::level_t logline::abbrev2level(const char *levelstr, size_t len)
+{
+    if (len == -1) {
+        len = strlen(levelstr);
+    }
+
+    if (len == 0) {
+        return LEVEL_UNKNOWN;
+    }
+
+    switch (toupper(levelstr[0])) {
+        case 'T':
+        return LEVEL_TRACE;
+        case 'D':
+        return LEVEL_DEBUG;
+        case 'I':
+        return LEVEL_INFO;
+        case 'W':
+        return LEVEL_WARNING;
+        case 'E':
+        return LEVEL_ERROR;
+        case 'C':
+        return LEVEL_CRITICAL;
+        case 'F':
+        return LEVEL_FATAL;
+    }
+
+    return LEVEL_UNKNOWN;
+}
+
+int logline::levelcmp(const char *l1, size_t l1_len, const char *l2, size_t l2_len)
+{
+    return abbrev2level(l1, l1_len) - abbrev2level(l2, l2_len);
+}
+
 const char *logline_value::value_names[VALUE__MAX] = {
     "null",
     "text",

src/log_format.hh

@@ -130,6 +130,11 @@ public:
 
     static level_t string2level(const char *levelstr, size_t len = -1, bool exact = false);
 
+    static level_t abbrev2level(const char *levelstr, size_t len = -1);
+
+    static int levelcmp(const char *l1, size_t l1_len,
+        const char *l2, size_t l2_len);
+
     /**
      * Construct a logline object with the given values.
      *

src/log_vtab_impl.cc

@@ -69,7 +69,7 @@ static string declare_table_statement(log_vtab_impl *vi)
         << "  log_part text collate naturalnocase,\n"
         << "  log_time datetime,\n"
         << "  log_idle_msecs int,\n"
-        << "  log_level text,\n";
+        << "  log_level text collate loglevel,\n";
     vi->get_columns(cols);
     vi->vi_column_count = cols.size();
     for (iter = cols.begin(); iter != cols.end(); iter++) {

test/test_sql_coll_func.sh

@@ -63,3 +63,25 @@ check_output "" <<EOF
 Row 0:
   Column 'file10.txt' < 'file2.txt' collate naturalcase: 0
 EOF
+
+
+run_test ./drive_sql "select 'w' < 'e' collate loglevel"
+
+check_output "" <<EOF
+Row 0:
+  Column 'w' < 'e' collate loglevel: 1
+EOF
+
+run_test ./drive_sql "select 'e' < 'w' collate loglevel"
+
+check_output "" <<EOF
+Row 0:
+  Column 'e' < 'w' collate loglevel: 0
+EOF
+
+run_test ./drive_sql "select 'info' collate loglevel between 'trace' and 'fatal'"
+
+check_output "" <<EOF
+Row 0:
+  Column 'info' collate loglevel between 'trace' and 'fatal': 1
+EOF