From 03e60f7da63aedab112748a4f1374f9914b85413 Mon Sep 17 00:00:00 2001
From: Wren Turkal <wt@penguintechs.org>
Date: Fri, 7 Aug 2020 01:05:24 -0700
Subject: [PATCH] Add log crate and add a generic logger.

This is the first step of integrating the log crate as the main way to
log messages from the kernel.

Also, reexport all log macros. This module should eventually be the
only logging API used in the kernel.

Signed-off-by: Wren Turkal <wt@penguintechs.org>
---
 Cargo.lock | 16 ++++++++++++++++
 Cargo.toml |  1 +
 src/log.rs | 18 ++++++++++++++++++
 3 files changed, 35 insertions(+)

diff --git a/Cargo.lock b/Cargo.lock
index 7eddfcf..5de4289 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -15,6 +15,11 @@ name = "cc"
 version = "1.0.52"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
+[[package]]
+name = "cfg-if"
+version = "0.1.10"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+
 [[package]]
 name = "goblin"
 version = "0.2.1"
@@ -31,6 +36,7 @@ dependencies = [
  "bitflags 1.2.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "goblin 0.2.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "linked_list_allocator 0.8.4 (registry+https://github.com/rust-lang/crates.io-index)",
+ "log 0.4.11 (registry+https://github.com/rust-lang/crates.io-index)",
  "paste 0.1.18 (registry+https://github.com/rust-lang/crates.io-index)",
  "raw-cpuid 8.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "redox_syscall 0.2.0",
@@ -64,6 +70,14 @@ dependencies = [
  "scopeguard 1.1.0 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
+[[package]]
+name = "log"
+version = "0.4.11"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "cfg-if 0.1.10 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
 [[package]]
 name = "paste"
 version = "0.1.18"
@@ -194,10 +208,12 @@ dependencies = [
 "checksum bit_field 0.10.0 (registry+https://github.com/rust-lang/crates.io-index)" = "a165d606cf084741d4ac3a28fb6e9b1eb0bd31f6cd999098cfddb0b2ab381dc0"
 "checksum bitflags 1.2.1 (registry+https://github.com/rust-lang/crates.io-index)" = "cf1de2fe8c75bc145a2f577add951f8134889b4795d47466a54a5c846d691693"
 "checksum cc 1.0.52 (registry+https://github.com/rust-lang/crates.io-index)" = "c3d87b23d6a92cd03af510a5ade527033f6aa6fa92161e2d5863a907d4c5e31d"
+"checksum cfg-if 0.1.10 (registry+https://github.com/rust-lang/crates.io-index)" = "4785bdd1c96b2a846b2bd7cc02e86b6b3dbf14e7e53446c4f54c92a361040822"
 "checksum goblin 0.2.1 (registry+https://github.com/rust-lang/crates.io-index)" = "ddd5e3132801a1ac34ac53b97acde50c4685414dd2f291b9ea52afa6f07468c8"
 "checksum linked_list_allocator 0.6.6 (registry+https://github.com/rust-lang/crates.io-index)" = "47de1a43fad0250ee197e9e124e5b5deab3d7b39d4428ae8a6d741ceb340c362"
 "checksum linked_list_allocator 0.8.4 (registry+https://github.com/rust-lang/crates.io-index)" = "e70e46c13c0e8374c26cec5752e3347ca1087d9711de8f45aa513a7700efd73d"
 "checksum lock_api 0.3.4 (registry+https://github.com/rust-lang/crates.io-index)" = "c4da24a77a3d8a6d4862d95f72e6fdb9c09a643ecdb402d754004a557f2bec75"
+"checksum log 0.4.11 (registry+https://github.com/rust-lang/crates.io-index)" = "4fabed175da42fed1fa0746b0ea71f412aa9d35e76e95e59b192c64b9dc2bf8b"
 "checksum paste 0.1.18 (registry+https://github.com/rust-lang/crates.io-index)" = "45ca20c77d80be666aef2b45486da86238fabe33e38306bd3118fe4af33fa880"
 "checksum paste-impl 0.1.18 (registry+https://github.com/rust-lang/crates.io-index)" = "d95a7db200b97ef370c8e6de0088252f7e0dfff7d047a28528e47456c0fc98b6"
 "checksum plain 0.2.3 (registry+https://github.com/rust-lang/crates.io-index)" = "b4596b6d070b27117e987119b4dac604f3c58cfb0b191112e24771b2faeac1a6"
diff --git a/Cargo.toml b/Cargo.toml
index 8630f68..9e650f9 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -12,6 +12,7 @@ crate-type = ["staticlib"]
 [dependencies]
 bitflags = "1.2.1"
 linked_list_allocator = "0.8.4"
+log = { version = "0.4" }
 raw-cpuid = "8.0.0"
 redox_syscall = { path = "syscall" }
 slab_allocator = { path = "slab_allocator", optional = true }
diff --git a/src/log.rs b/src/log.rs
index d11dbfa..25a2c5c 100644
--- a/src/log.rs
+++ b/src/log.rs
@@ -33,3 +33,21 @@ impl Log {
         }
     }
 }
+
+struct RedoxLogger {
+    log_func: fn(&log::Record),
+}
+
+impl ::log::Log for RedoxLogger {
+    fn enabled(&self, _: &log::Metadata<'_>) -> bool {
+        false
+    }
+    fn log(&self, record: &log::Record<'_>) {
+        (self.log_func)(&record)
+    }
+    fn flush(&self) {}
+}
+
+static _LOGGER: RedoxLogger = RedoxLogger { log_func: |_| {} };
+
+pub use log::{debug, error, info, trace, warn};