chore: Improve logging of file read failures

8 files changed, 17 insertions, 11 deletions

diff --git a/src/Args.cpp b/src/Args.cpp
index d4077a35..50cfa672 100644
--- a/src/Args.cpp
+++ b/src/Args.cpp
@@ -20,6 +20,7 @@
 
 #include "Util.hpp"
 
+#include <Logging.hpp>
 #include <core/exceptions.hpp>
 #include <util/file.hpp>
 #include <util/string.hpp>
@@ -51,6 +52,7 @@ Args::from_atfile(const std::string& filename, AtFileFormat format)
 {
   const auto argtext = util::read_file<std::string>(filename);
   if (!argtext) {
+    LOG("Failed to read atfile {}: {}", filename, argtext.error());
     return std::nullopt;
   }
 
diff --git a/src/Depfile.cpp b/src/Depfile.cpp
index 2d721a6c..f1ef39a1 100644
--- a/src/Depfile.cpp
+++ b/src/Depfile.cpp
@@ -130,7 +130,9 @@ make_paths_relative_in_output_dep(const Context& ctx)
   const std::string& output_dep = ctx.args_info.output_dep;
   const auto file_content = util::read_file<std::string>(output_dep);
   if (!file_content) {
-    LOG("Cannot open dependency file {}: {}", output_dep, file_content.error());
+    LOG("Failed to read dependency file {}: {}",
+        output_dep,
+        file_content.error());
     return;
   }
   const auto new_content = rewrite_source_paths(ctx, *file_content);
diff --git a/src/ccache.cpp b/src/ccache.cpp
index e701e204..392818ff 100644
--- a/src/ccache.cpp
+++ b/src/ccache.cpp
@@ -452,7 +452,7 @@ process_preprocessed_file(Context& ctx, Hash& hash, const std::string& path)
 {
   auto data = util::read_file<std::string>(path);
   if (!data) {
-    LOG("Failed reading {}: {}", path, data.error());
+    LOG("Failed to read {}: {}", path, data.error());
     return nonstd::make_unexpected(Statistic::internal_error);
   }
 
@@ -633,7 +633,7 @@ result_key_from_depfile(Context& ctx, Hash& hash)
   const auto file_content =
     util::read_file<std::string>(ctx.args_info.output_dep);
   if (!file_content) {
-    LOG("Cannot open dependency file {}: {}",
+    LOG("Failed to read dependency file {}: {}",
         ctx.args_info.output_dep,
         file_content.error());
     return std::nullopt;
@@ -763,7 +763,9 @@ do_execute(Context& ctx, Args& args, const bool capture_stdout = true)
   if (capture_stdout) {
     auto stdout_data_result = util::read_file<util::Bytes>(tmp_stdout.path);
     if (!stdout_data_result) {
-      // The stdout file was removed - cleanup in progress? Better bail out.
+      LOG("Failed to read {} (cleanup in progress?): {}",
+          tmp_stdout.path,
+          stdout_data_result.error());
       return nonstd::make_unexpected(Statistic::missing_cache_file);
     }
     stdout_data = *stdout_data_result;
@@ -771,7 +773,9 @@ do_execute(Context& ctx, Args& args, const bool capture_stdout = true)
 
   auto stderr_data_result = util::read_file<util::Bytes>(tmp_stderr.path);
   if (!stderr_data_result) {
-    // The stdout file was removed - cleanup in progress? Better bail out.
+    LOG("Failed to read {} (cleanup in progress?): {}",
+        tmp_stderr.path,
+        stderr_data_result.error());
     return nonstd::make_unexpected(Statistic::missing_cache_file);
   }
 
diff --git a/src/core/mainoptions.cpp b/src/core/mainoptions.cpp
index 1f6e651c..2283162f 100644
--- a/src/core/mainoptions.cpp
+++ b/src/core/mainoptions.cpp
@@ -175,7 +175,7 @@ read_from_path_or_stdin(const std::string& path)
     const auto result = util::read_file<std::vector<uint8_t>>(path);
     if (!result) {
       return nonstd::make_unexpected(
-        FMT("Failed to read from {}: {}", path, result.error()));
+        FMT("Failed to read {}: {}", path, result.error()));
     }
     return *result;
   }
diff --git a/src/hashutil.cpp b/src/hashutil.cpp
index 990561ff..8d7151d6 100644
--- a/src/hashutil.cpp
+++ b/src/hashutil.cpp
@@ -202,6 +202,7 @@ do_hash_file(const Context& ctx,
 
   const auto data = util::read_file<std::string>(path, size_hint);
   if (!data) {
+    LOG("Failed to read {}: {}", path, data.error());
     return HASH_SOURCE_CODE_ERROR;
   }
 
diff --git a/src/storage/local/StatsFile.cpp b/src/storage/local/StatsFile.cpp
index b00fc82e..4332d80e 100644
--- a/src/storage/local/StatsFile.cpp
+++ b/src/storage/local/StatsFile.cpp
@@ -38,7 +38,7 @@ StatsFile::read() const
 
   const auto data = util::read_file<std::string>(m_path);
   if (!data) {
-    // Ignore.
+    // A nonexistent stats file is OK.
     return counters;
   }
 
diff --git a/src/util/LockFile.cpp b/src/util/LockFile.cpp
index 0d7e96e8..f90b7626 100644
--- a/src/util/LockFile.cpp
+++ b/src/util/LockFile.cpp
@@ -178,7 +178,6 @@ LockFile::do_acquire(const bool blocking)
     }
 
     int saved_errno = errno;
-    LOG("Could not acquire {}: {}", m_lock_file, strerror(saved_errno));
     if (saved_errno == ENOENT) {
       // Directory doesn't exist?
       if (Util::create_dir(Util::dir_name(m_lock_file))) {
@@ -186,6 +185,7 @@ LockFile::do_acquire(const bool blocking)
         continue;
       }
     }
+    LOG("Could not acquire {}: {}", m_lock_file, strerror(saved_errno));
 
     if (saved_errno == EPERM) {
       // The file system does not support symbolic links. We have no choice but
diff --git a/src/util/file.cpp b/src/util/file.cpp
index 5ddc05bb..db0f4e83 100644
--- a/src/util/file.cpp
+++ b/src/util/file.cpp
@@ -111,7 +111,6 @@ read_file(const std::string& path, size_t size_hint)
   if (size_hint == 0) {
     const auto stat = Stat::stat(path);
     if (!stat) {
-      LOG("Failed to stat {}: {}", path, strerror(errno));
       return nonstd::make_unexpected(strerror(errno));
     }
     size_hint = stat.size();
@@ -129,7 +128,6 @@ read_file(const std::string& path, size_t size_hint)
   }();
   Fd fd(open(path.c_str(), open_flags));
   if (!fd) {
-    LOG("Failed to open {}: {}", path, strerror(errno));
     return nonstd::make_unexpected(strerror(errno));
   }
 
@@ -156,7 +154,6 @@ read_file(const std::string& path, size_t size_hint)
   }
 
   if (ret == -1) {
-    LOG("Failed to read {}: {}", path, strerror(errno));
     return nonstd::make_unexpected(strerror(errno));
   }