[spectro] log_time must be in ascending order

src/db_sub_source.hh

@@ -201,7 +201,13 @@ public:
                 tv.tv_sec = -1;
                 tv.tv_usec = -1;
             }
-            this->dls_time_column.push_back(tv);
+            if (!this->dls_time_column.empty() && tv < this->dls_time_column.back()) {
+                this->dls_time_column_index = -1;
+                this->dls_time_column.clear();
+            }
+            else {
+                this->dls_time_column.push_back(tv);
+            }
         }
 
         this->dls_rows.back().push_back(colstr);

src/lnav_commands.cc

@@ -2606,7 +2606,7 @@ public:
         this->dsvs_column_index = dls.column_name_to_index(this->dsvs_colname);
 
         if (!dls.has_log_time_column()) {
-            this->dsvs_error_msg = "no 'log_time' column found, unable to create spectrogram";
+            this->dsvs_error_msg = "no 'log_time' column found or not in ascending order, unable to create spectrogram";
             return;
         }
 

src/lnav_util.hh

@@ -258,6 +258,12 @@ bool operator<(time_t left, const struct timeval &right) {
     return left < right.tv_sec;
 };
 
+inline
+bool operator<(const struct timeval &left, const struct timeval &right) {
+    return left.tv_sec < right.tv_sec ||
+        ((left.tv_sec == right.tv_usec) && (left.tv_usec < right.tv_usec));
+};
+
 struct date_time_scanner {
     date_time_scanner() : dts_keep_base_tz(false),
                           dts_local_time(false),

test/test_sql.sh

@@ -77,7 +77,7 @@ run_test ${lnav_test} -n \
     ${test_dir}/logfile_access_log.0
 
 check_error_output "spectrogram worked without log_time?" <<EOF
-error: no 'log_time' column found, unable to create spectrogram
+error: no 'log_time' column found or not in ascending order, unable to create spectrogram
 EOF
 
 run_test ${lnav_test} -n \
@@ -98,6 +98,15 @@ check_error_output "spectrogram worked with non-numeric column?" <<EOF
 error: column is not numeric -- c_ip
 EOF
 
+run_test ${lnav_test} -n \
+    -c ';select log_time,sc_bytes from access_log order by log_time desc' \
+    -c ':spectrogram sc_bytes' \
+    ${test_dir}/logfile_access_log.0
+
+check_error_output "spectrogram worked with unordered log_time?" <<EOF
+error: no 'log_time' column found or not in ascending order, unable to create spectrogram
+EOF
+
 
 run_test ${lnav_test} -n \
     -c ";select log_time,log_actual_time from syslog_log" \