Merge pull request neovim#29016 from bfredl/shadareader

refactor(shada): remove ShaDaReadDef secondary wrapper

src/nvim/os/fileio.c

@@ -126,6 +126,7 @@ int file_open_fd(FileDescriptor *const ret_fp, const int fd, const int flags)
     ret_fp->rv->data = ret_fp;
     ret_fp->rv->full_cb = (rbuffer_callback)&file_rb_write_full_cb;
   }
+  ret_fp->bytes_read = 0;
   return 0;
 }
 
@@ -140,6 +141,18 @@ int file_open_stdin(FileDescriptor *fp)
   return error;
 }
 
+/// opens buffer for reading
+void file_open_buffer(FileDescriptor *ret_fp, char *data, size_t len)
+{
+  ret_fp->wr = false;
+  ret_fp->non_blocking = false;
+  ret_fp->fd = -1;
+  ret_fp->eof = true;
+  ret_fp->rv = rbuffer_new_wrap_buf(data, len);
+  ret_fp->_error = 0;
+  ret_fp->bytes_read = 0;
+}
+
 /// Close file and free its buffer
 ///
 /// @param[in,out]  fp  File to close.
@@ -149,6 +162,11 @@ int file_open_stdin(FileDescriptor *fp)
 int file_close(FileDescriptor *const fp, const bool do_fsync)
   FUNC_ATTR_NONNULL_ALL
 {
+  if (fp->fd < 0) {
+    rbuffer_free(fp->rv);
+    return 0;
+  }
+
   const int flush_error = (do_fsync ? file_fsync(fp) : file_flush(fp));
   const int close_error = os_close(fp->fd);
   rbuffer_free(fp->rv);
@@ -294,6 +312,7 @@ ptrdiff_t file_read(FileDescriptor *const fp, char *const ret_buf, const size_t
                                         fp->non_blocking);
         if (r_ret >= 0) {
           read_remaining -= (size_t)r_ret;
+          fp->bytes_read += (size - read_remaining);
           return (ptrdiff_t)(size - read_remaining);
         } else if (r_ret < 0) {
           return r_ret;
@@ -314,6 +333,7 @@ ptrdiff_t file_read(FileDescriptor *const fp, char *const ret_buf, const size_t
       called_read = true;
     }
   }
+  fp->bytes_read += (size - read_remaining);
   return (ptrdiff_t)(size - read_remaining);
 }
 

src/nvim/os/fileio_defs.h

@@ -1,6 +1,7 @@
 #pragma once
 
 #include <stdbool.h>
+#include <stdint.h>
 
 #include "nvim/func_attr.h"
 #include "nvim/rbuffer_defs.h"
@@ -13,6 +14,7 @@ typedef struct {
   bool wr;            ///< True if file is in write mode.
   bool eof;           ///< True if end of file was encountered.
   bool non_blocking;  ///< True if EAGAIN should not restart syscalls.
+  uint64_t bytes_read;  ///< total bytes read so far
 } FileDescriptor;
 
 static inline bool file_eof(const FileDescriptor *fp)

src/nvim/rbuffer.c

@@ -29,6 +29,23 @@ RBuffer *rbuffer_new(size_t capacity)
   return rv;
 }
 
+/// Creates a new `RBuffer` instance for reading from a buffer.
+///
+/// Must not be used with any write function like rbuffer_write_ptr or rbuffer_produced!
+RBuffer *rbuffer_new_wrap_buf(char *data, size_t len)
+  FUNC_ATTR_WARN_UNUSED_RESULT FUNC_ATTR_NONNULL_RET
+{
+  RBuffer *rv = xcalloc(1, sizeof(RBuffer));
+  rv->full_cb = rv->nonfull_cb = NULL;
+  rv->data = NULL;
+  rv->size = len;
+  rv->read_ptr = data;
+  rv->write_ptr = data + len;
+  rv->end_ptr = NULL;
+  rv->temp = NULL;
+  return rv;
+}
+
 void rbuffer_free(RBuffer *buf) FUNC_ATTR_NONNULL_ALL
 {
   xfree(buf->temp);
@@ -129,7 +146,7 @@ void rbuffer_consumed(RBuffer *buf, size_t count)
   assert(count <= buf->size);
 
   buf->read_ptr += count;
-  if (buf->read_ptr >= buf->end_ptr) {
+  if (buf->end_ptr && buf->read_ptr >= buf->end_ptr) {
     buf->read_ptr -= rbuffer_capacity(buf);
   }