system-config-api: add functions to read/write time and timezone

Signed-off-by: Dietmar Maurer <dietmar@proxmox.com>

proxmox-system-config-api/Cargo.toml

@@ -19,9 +19,10 @@ serde_json = { workspace = true }
 
 proxmox-sys = { workspace = true, optional = true }
 proxmox-schema = { workspace = true, features = ["api-macro", "api-types"] }
+proxmox-time = { workspace = true, optional = true }
 proxmox-product-config = { workspace = true, optional = true }
 
 
 [features]
 default = [ "proxmox-product-config/default" ]
-impl =  [ "dep:proxmox-sys", "proxmox-product-config/impl"]
+impl =  [ "dep:proxmox-sys", "dep:proxmox-time", "proxmox-product-config/impl"]

proxmox-system-config-api/src/api_types.rs

@@ -2,6 +2,7 @@ use serde::{Deserialize, Serialize};
 
 use proxmox_schema::api;
 use proxmox_schema::api_types::IP_FORMAT;
+use proxmox_schema::api_types::TIME_ZONE_SCHEMA;
 use proxmox_schema::Schema;
 use proxmox_schema::StringSchema;
 
@@ -80,7 +81,6 @@ pub struct ResolvConfWithDigest {
     pub digest: ConfigDigest,
 }
 
-
 #[api()]
 #[derive(Serialize, Deserialize)]
 #[serde(rename_all = "kebab-case")]
@@ -93,3 +93,28 @@ pub enum DeletableResolvConfProperty {
     /// Delete third nameserver entry
     Dns3,
 }
+
+#[api(
+    properties: {
+        timezone: {
+            schema: TIME_ZONE_SCHEMA,
+        },
+        time: {
+            type: i64,
+            description: "Seconds since 1970-01-01 00:00:00 UTC.",
+            minimum: 1_297_163_644,
+        },
+        localtime: {
+            type: i64,
+            description: "Seconds since 1970-01-01 00:00:00 UTC. (local time)",
+            minimum: 1_297_163_644,
+        },
+    }
+)]
+#[derive(Serialize, Deserialize)]
+/// Server time and timezone.
+pub struct ServerTimeInfo {
+    pub timezone: String,
+    pub time: i64,
+    pub localtime: i64,
+}

proxmox-system-config-api/src/lib.rs

@@ -1,4 +1,5 @@
 mod api_types;
+pub use api_types::ServerTimeInfo;
 pub use api_types::{DeletableResolvConfProperty, ResolvConf, ResolvConfWithDigest};
 pub use api_types::{
     FIRST_DNS_SERVER_SCHEMA, SEARCH_DOMAIN_SCHEMA, SECOND_DNS_SERVER_SCHEMA,
@@ -6,6 +7,7 @@ pub use api_types::{
 };
 
 #[cfg(feature = "impl")]
-mod resolv_conf;
+pub mod resolv_conf;
+
 #[cfg(feature = "impl")]
-pub use resolv_conf::*;
+pub mod time;

proxmox-system-config-api/src/time.rs

@@ -0,0 +1,55 @@
+use anyhow::{bail, format_err, Error};
+
+use proxmox_product_config::replace_system_config;
+use proxmox_sys::fs::file_read_firstline;
+
+use crate::api_types::ServerTimeInfo;
+
+pub fn read_etc_localtime() -> Result<String, Error> {
+    // use /etc/timezone
+    if let Ok(line) = file_read_firstline("/etc/timezone") {
+        return Ok(line.trim().to_owned());
+    }
+
+    // otherwise guess from the /etc/localtime symlink
+    let link = std::fs::read_link("/etc/localtime")
+        .map_err(|err| format_err!("failed to guess timezone - {}", err))?;
+
+    let link = link.to_string_lossy();
+    match link.rfind("/zoneinfo/") {
+        Some(pos) => Ok(link[(pos + 10)..].to_string()),
+        None => Ok(link.to_string()),
+    }
+}
+
+pub fn set_timezone(timezone: String) -> Result<(), Error> {
+    let path = std::path::PathBuf::from(format!("/usr/share/zoneinfo/{}", timezone));
+
+    if !path.exists() {
+        bail!("No such timezone.");
+    }
+
+    replace_system_config("/etc/timezone", timezone.as_bytes())?;
+
+    let _ = std::fs::remove_file("/etc/localtime");
+
+    use std::os::unix::fs::symlink;
+    symlink(path, "/etc/localtime")?;
+
+    Ok(())
+}
+
+/// Read server time and time zone settings.
+pub fn get_server_time_info() -> Result<ServerTimeInfo, Error> {
+    let time = proxmox_time::epoch_i64();
+    let tm = proxmox_time::localtime(time)?;
+    let offset = tm.tm_gmtoff;
+
+    let localtime = time + offset;
+
+    Ok(ServerTimeInfo {
+        timezone: read_etc_localtime()?,
+        time: time,
+        localtime: localtime,
+    })
+}