From a4a1669896250bef6d1c31e7880cdcb0857a797f Mon Sep 17 00:00:00 2001
From: Junichi Uekawa <uekawa@google.com>
Date: Tue, 15 Mar 2022 11:32:24 +0900
Subject: [PATCH] argument: move out parse_hex_or_decimal.

There's some common code.

BUG=None
TEST=build

Change-Id: I3845acfa9dc6370ef4f8e9eb1ef3a67b339aa7f3
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/crosvm/+/3524361
Reviewed-by: Daniel Verkamp <dverkamp@chromium.org>
Tested-by: kokoro <noreply+kokoro@google.com>
Commit-Queue: Junichi Uekawa <uekawa@chromium.org>
---
 src/argument.rs | 31 +++++++++++++++++++++++++------
 src/main.rs     | 12 +-----------
 2 files changed, 26 insertions(+), 17 deletions(-)

diff --git a/src/argument.rs b/src/argument.rs
index b86ec950fb..42211fdd55 100644
--- a/src/argument.rs
+++ b/src/argument.rs
@@ -395,6 +395,21 @@ pub fn print_help(program_name: &str, required_arg: &str, args: &[Argument]) {
     }
 }
 
+pub fn parse_hex_or_decimal(maybe_hex_string: &str) -> Result<u64> {
+    // Parse string starting with 0x as hex and others as numbers.
+    if let Some(hex_string) = maybe_hex_string.strip_prefix("0x") {
+        u64::from_str_radix(hex_string, 16)
+    } else if let Some(hex_string) = maybe_hex_string.strip_prefix("0X") {
+        u64::from_str_radix(hex_string, 16)
+    } else {
+        u64::from_str(maybe_hex_string)
+    }
+    .map_err(|e| Error::InvalidValue {
+        value: maybe_hex_string.to_string(),
+        expected: e.to_string(),
+    })
+}
+
 pub struct KeyValuePair<'a> {
     context: &'a str,
     key: &'a str,
@@ -433,12 +448,7 @@ impl<'a> KeyValuePair<'a> {
         <T as TryFrom<u64>>::Error: std::error::Error,
     {
         let val = self.value()?;
-        let numres = if val.starts_with("0x") || val.starts_with("0X") {
-            u64::from_str_radix(&val[2..], 16)
-        } else {
-            u64::from_str(val)
-        };
-        let num = self.handle_parse_err(numres)?;
+        let num = parse_hex_or_decimal(val)?;
         self.handle_parse_err(T::try_from(num))
     }
 
@@ -704,4 +714,13 @@ mod tests {
         assert!(kv.parse::<u32>().is_err());
         assert!(kv.parse_numeric::<u32>().is_err());
     }
+
+    #[test]
+    fn parse_hex_or_decimal_simple() {
+        assert_eq!(parse_hex_or_decimal("15").unwrap(), 15);
+        assert_eq!(parse_hex_or_decimal("0x15").unwrap(), 0x15);
+        assert_eq!(parse_hex_or_decimal("0X15").unwrap(), 0x15);
+        assert!(parse_hex_or_decimal("0xz").is_err());
+        assert!(parse_hex_or_decimal("hello world").is_err());
+    }
 }
diff --git a/src/main.rs b/src/main.rs
index edab4b2fac..2277286c53 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -25,7 +25,7 @@ use crosvm::platform::GpuRenderServerParameters;
 #[cfg(feature = "direct")]
 use crosvm::DirectIoOption;
 use crosvm::{
-    argument::{self, print_help, set_arguments, Argument},
+    argument::{self, parse_hex_or_decimal, print_help, set_arguments, Argument},
     platform, BindMount, Config, DiskOption, Executable, FileBackedMappingParameters, GidMap,
     SharedDir, TouchDeviceOption, VfioCommand, VhostUserFsOption, VhostUserOption,
     VhostUserWlOption, VhostVsockDeviceParameter, VvuOption, DISK_ID_LEN,
@@ -905,16 +905,6 @@ fn parse_battery_options(s: Option<&str>) -> argument::Result<BatteryType> {
     Ok(battery_type)
 }
 
-#[cfg(feature = "direct")]
-fn parse_hex_or_decimal(maybe_hex_string: &str) -> Result<u64, std::num::ParseIntError> {
-    // Parse string starting with 0x as hex and others as numbers.
-    let without_prefix = maybe_hex_string.strip_prefix("0x");
-    match without_prefix {
-        Some(hex_string) => u64::from_str_radix(hex_string, 16),
-        None => u64::from_str(maybe_hex_string),
-    }
-}
-
 #[cfg(feature = "direct")]
 fn parse_direct_io_options(s: Option<&str>) -> argument::Result<DirectIoOption> {
     let s = s.ok_or(argument::Error::ExpectedValue(String::from(