Implement text path trimming for shorter paths.

3 files changed, 53 insertions, 1 deletions

diff --git a/src/common/logging/text_formatter.cpp b/src/common/logging/text_formatter.cpp
index b603ead13..88deb150e 100644
--- a/src/common/logging/text_formatter.cpp
+++ b/src/common/logging/text_formatter.cpp
@@ -14,8 +14,33 @@
 #include "common/logging/log.h"
 #include "common/logging/text_formatter.h"
 
+#include "common/string_util.h"
+
 namespace Log {
 
+// TODO(bunnei): This should be moved to a generic path manipulation library
+const char* TrimSourcePath(const char* path, const char* root) {
+    const char* p = path;
+
+    while (*p != '\0') {
+        const char* next_slash = p;
+        while (*next_slash != '\0' && *next_slash != '/' && *next_slash != '\\') {
+            ++next_slash;
+        }
+
+        bool is_src = Common::ComparePartialString(p, next_slash, root);
+        p = next_slash;
+
+        if (*p != '\0') {
+            ++p;
+        }
+        if (is_src) {
+            path = p;
+        }
+    }
+    return path;
+}
+
 void FormatLogMessage(const Entry& entry, char* out_text, size_t text_len) {
     unsigned int time_seconds    = static_cast<unsigned int>(entry.timestamp.count() / 1000000);
     unsigned int time_fractional = static_cast<unsigned int>(entry.timestamp.count() % 1000000);
@@ -25,7 +50,7 @@ void FormatLogMessage(const Entry& entry, char* out_text, size_t text_len) {
 
     snprintf(out_text, text_len, "[%4u.%06u] %s <%s> %s: %s",
         time_seconds, time_fractional, class_name, level_name,
-        entry.location.c_str(), entry.message.c_str());
+        TrimSourcePath(entry.location.c_str()), entry.message.c_str());
 }
 
 static void ChangeConsoleColor(Level level) {
diff --git a/src/common/logging/text_formatter.h b/src/common/logging/text_formatter.h
index 6c2a6f1ea..04164600f 100644
--- a/src/common/logging/text_formatter.h
+++ b/src/common/logging/text_formatter.h
@@ -12,6 +12,18 @@ namespace Log {
 class Logger;
 struct Entry;
 
+/**
+ * Attempts to trim an arbitrary prefix from `path`, leaving only the part starting at `root`. It's
+ * intended to be used to strip a system-specific build directory from the `__FILE__` macro,
+ * leaving only the path relative to the sources root.
+ *
+ * @param path The input file path as a null-terminated string
+ * @param root The name of the root source directory as a null-terminated string. Path up to and
+ *             including the last occurence of this name will be stripped
+ * @return A pointer to the same string passed as `path`, but starting at the trimmed portion
+ */
+const char* TrimSourcePath(const char* path, const char* root = "src");
+
 /// Formats a log entry into the provided text buffer.
 void FormatLogMessage(const Entry& entry, char* out_text, size_t text_len);
 /// Formats and prints a log entry to stderr.
diff --git a/src/common/string_util.h b/src/common/string_util.h
index ae5bbadad..7d75691b1 100644
--- a/src/common/string_util.h
+++ b/src/common/string_util.h
@@ -115,4 +115,19 @@ inline std::string UTF8ToTStr(const std::string& str)
 
 #endif
 
+/**
+ * Compares the string defined by the range [`begin`, `end`) to the null-terminated C-string
+ * `other` for equality.
+ */
+template <typename InIt>
+bool ComparePartialString(InIt begin, InIt end, const char* other) {
+    for (; begin != end && *other != '\0'; ++begin, ++other) {
+        if (*begin != *other) {
+            return false;
+        }
+    }
+    // Only return true if both strings finished at the same point
+    return (begin == end) == (*other == '\0');
+}
+
 }