Refactor buffer creation and reloading to be more explicit

Reloading used to be implicit in the buffer creation function,
which is not always nice, as code that explicitely wanted to
reload a buffer could not say so.

1 files changed, 65 insertions, 31 deletions

diff --git a/src/buffer_utils.cc b/src/buffer_utils.cc
index 0bebf5d6..e2fdbfcb 100644
--- a/src/buffer_utils.cc
+++ b/src/buffer_utils.cc
@@ -2,6 +2,7 @@
 
 #include "buffer_manager.hh"
 #include "event_manager.hh"
+#include "file.hh"
 
 #include <unistd.h>
 #include <sys/select.h>
@@ -46,50 +47,83 @@ ByteCount get_byte_to_column(const Buffer& buffer, CharCount tabstop, CharCoord
     return (int)(it - line.begin());
 }
 
-Buffer* create_buffer_from_data(StringView data, StringView name,
-                                Buffer::Flags flags, timespec fs_timestamp)
+struct BufferData
 {
-    bool bom = false, crlf = false;
+    BufferLines lines;
+    bool bom = false;
+    bool crlf = false;
 
-    const char* pos = data.begin();
-    if (data.length() >= 3 and
-       data[0_byte] == '\xEF' and data[1_byte] == '\xBB' and data[2_byte] == '\xBF')
+    BufferData(StringView data)
     {
-        bom = true;
-        pos = data.begin() + 3;
-    }
+        const char* pos = data.begin();
+        if (data.length() >= 3 and
+           data[0_byte] == '\xEF' and data[1_byte] == '\xBB' and data[2_byte] == '\xBF')
+        {
+            bom = true;
+            pos = data.begin() + 3;
+        }
 
-    BufferLines lines;
-    while (pos < data.end())
-    {
-        const char* line_end = pos;
-        while (line_end < data.end() and *line_end != '\r' and *line_end != '\n')
-             ++line_end;
+        while (pos < data.end())
+        {
+            const char* line_end = pos;
+            while (line_end < data.end() and *line_end != '\r' and *line_end != '\n')
+                 ++line_end;
 
-        lines.emplace_back(StringData::create({pos, line_end}, '\n'));
+            lines.emplace_back(StringData::create({pos, line_end}, '\n'));
 
-        if (line_end+1 != data.end() and *line_end == '\r' and *(line_end+1) == '\n')
-        {
-            crlf = true;
-            pos = line_end + 2;
+            if (line_end+1 != data.end() and *line_end == '\r' and *(line_end+1) == '\n')
+            {
+                crlf = true;
+                pos = line_end + 2;
+            }
+            else
+                pos = line_end + 1;
         }
-        else
-            pos = line_end + 1;
     }
 
-    Buffer* buffer = BufferManager::instance().get_buffer_ifp(name);
-    if (buffer)
-        buffer->reload(std::move(lines), fs_timestamp);
-    else
-        buffer = new Buffer{name.str(), flags, std::move(lines), fs_timestamp};
+    void apply_options(Buffer& buffer) const
+    {
+        OptionManager& options = buffer.options();
+        options.get_local_option("eolformat").set<String>(crlf ? "crlf" : "lf");
+        options.get_local_option("BOM").set<String>(bom ? "utf-8" : "no");
+    }
+};
 
-    OptionManager& options = buffer->options();
-    options.get_local_option("eolformat").set<String>(crlf ? "crlf" : "lf");
-    options.get_local_option("BOM").set<String>(bom ? "utf-8" : "no");
+Buffer* create_file_buffer(StringView filename)
+{
+    if (MappedFile file_data{filename})
+        return create_buffer({ file_data.data, (int)file_data.st.st_size }, filename,
+                             Buffer::Flags::File, file_data.st.st_mtim);
+    return nullptr;
+}
 
+bool reload_file_buffer(Buffer& buffer)
+{
+    kak_assert(buffer.flags() & Buffer::Flags::File);
+    if (MappedFile file_data{buffer.name()})
+    {
+        reload_buffer(buffer,  { file_data.data, (int)file_data.st.st_size }, file_data.st.st_mtim);
+        return true;
+    }
+    return false;
+}
+
+Buffer* create_buffer(StringView data, StringView name, Buffer::Flags flags,
+                      timespec fs_timestamp)
+{
+    BufferData buf_data(data);
+    Buffer* buffer = new Buffer{name.str(), flags, std::move(buf_data.lines), fs_timestamp};
+    buf_data.apply_options(*buffer);
     return buffer;
 }
 
+void reload_buffer(Buffer& buffer, StringView data, timespec fs_timestamp)
+{
+    BufferData buf_data(data);
+    buffer.reload(std::move(buf_data.lines), fs_timestamp);
+    buf_data.apply_options(buffer);
+}
+
 Buffer* create_fifo_buffer(String name, int fd, bool scroll)
 {
     static ValueId s_fifo_watcher_id = ValueId::get_free_id();
@@ -185,7 +219,7 @@ void write_to_debug_buffer(StringView str)
     else
     {
         String line = str + ((str.empty() or str.back() != '\n') ? "\n" : "");
-        create_buffer_from_data(line, debug_buffer_name, Buffer::Flags::NoUndo);
+        create_buffer(line, debug_buffer_name, Buffer::Flags::NoUndo, InvalidTime);
     }
 }