From 2742c7f84977e63ee8189ed266fe41da1adc5cce Mon Sep 17 00:00:00 2001
From: Mira Limbeck <m.limbeck@proxmox.com>
Date: Wed, 28 Jun 2023 10:54:28 +0200
Subject: [PATCH] add compatibility with API/Tracking Center

The API assumes the timestamps to be in the local timezone rather than
UTC. It then subtracts the timezone offset leading to wrong values when
timestamps are in UTC, but timezone is not.

For compatibility, add the local timezone to those timestamps.

Reviewed-by: Dominik Csapak <d.csapak@proxmox.com>
Tested-by: Dominik Csapak <d.csapak@proxmox.com>
Signed-off-by: Mira Limbeck <m.limbeck@proxmox.com>
---
 src/main.rs | 43 ++++++++++++++++++++++++++++++++-----------
 1 file changed, 32 insertions(+), 11 deletions(-)

diff --git a/src/main.rs b/src/main.rs
index e7bffd8..e55f17b 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -1737,6 +1737,8 @@ struct Parser {
     string_match: bool,
 
     lines: u64,
+
+    timezone_offset: time_t,
 }
 
 impl Parser {
@@ -1762,6 +1764,7 @@ impl Parser {
             ctime: 0,
             string_match: false,
             lines: 0,
+            timezone_offset: ltime.tm_gmtoff,
         })
     }
 
@@ -1836,7 +1839,12 @@ impl Parser {
             let line = &buffer[0..size - 1];
             let complete_line = line;
 
-            let (time, line) = match parse_time(line, self.current_year, self.current_month) {
+            let (time, line) = match parse_time(
+                line,
+                self.current_year,
+                self.current_month,
+                self.timezone_offset,
+            ) {
                 Some(t) => t,
                 None => continue,
             };
@@ -1920,9 +1928,12 @@ impl Parser {
                         if size == 0 {
                             return count;
                         }
-                        if let Some((time, _)) =
-                            parse_time(&buffer[0..size], self.current_year, self.current_month)
-                        {
+                        if let Some((time, _)) = parse_time(
+                            &buffer[0..size],
+                            self.current_year,
+                            self.current_month,
+                            self.timezone_offset,
+                        ) {
                             // found the earliest file in the time frame
                             if time < self.options.start {
                                 break;
@@ -1937,9 +1948,12 @@ impl Parser {
                         if size == 0 {
                             return count;
                         }
-                        if let Some((time, _)) =
-                            parse_time(&buffer[0..size], self.current_year, self.current_month)
-                        {
+                        if let Some((time, _)) = parse_time(
+                            &buffer[0..size],
+                            self.current_year,
+                            self.current_month,
+                            self.timezone_offset,
+                        ) {
                             if time < self.options.start {
                                 break;
                             }
@@ -2235,11 +2249,17 @@ fn parse_number(data: &[u8], max_digits: usize) -> Option<(usize, &[u8])> {
 }
 
 /// Parse time. Returns a tuple of (parsed_time, remaining_text) or None.
-fn parse_time(data: &'_ [u8], cur_year: i64, cur_month: i64) -> Option<(time_t, &'_ [u8])> {
-    parse_time_with_year(data).or_else(|| parse_time_no_year(data, cur_year, cur_month))
+fn parse_time(
+    data: &'_ [u8],
+    cur_year: i64,
+    cur_month: i64,
+    timezone_offset: time_t,
+) -> Option<(time_t, &'_ [u8])> {
+    parse_time_with_year(data, timezone_offset)
+        .or_else(|| parse_time_no_year(data, cur_year, cur_month))
 }
 
-fn parse_time_with_year(data: &'_ [u8]) -> Option<(time_t, &'_ [u8])> {
+fn parse_time_with_year(data: &'_ [u8], timezone_offset: time_t) -> Option<(time_t, &'_ [u8])> {
     let mut timestamp_buffer = [0u8; 25];
 
     let count = data.iter().take_while(|b| **b != b' ').count();
@@ -2266,7 +2286,8 @@ fn parse_time_with_year(data: &'_ [u8]) -> Option<(time_t, &'_ [u8])> {
     match proxmox_time::parse_rfc3339(unsafe {
         std::str::from_utf8_unchecked(&timestamp_buffer[0..timestamp_len])
     }) {
-        Ok(ltime) => Some((ltime, data)),
+        // TODO handle timezone offset in old code path instead
+        Ok(ltime) => Some((ltime + timezone_offset, data)),
         Err(_err) => None,
     }
 }