diff options
Diffstat (limited to 'src/server/buffer.cpp')
-rw-r--r-- | src/server/buffer.cpp | 45 |
1 files changed, 45 insertions, 0 deletions
diff --git a/src/server/buffer.cpp b/src/server/buffer.cpp new file mode 100644 index 0000000..7b4c92d --- /dev/null +++ b/src/server/buffer.cpp @@ -0,0 +1,45 @@ +struct Buffer { + const char *name; + Page *storage; + + Buffer(const char *name) : name(name), storage(new Page()) {} + + void free_storage() { + while (storage) { + Page *iter = storage; + storage = storage->next; + delete iter; + } + } + + void read_file(const char *pathname) { + free_storage(); + int file = open(pathname, O_RDONLY); + storage = new Page(); + int bytes_read = read(file, storage->elements, PAGE_SIZE); + Page *iter = storage; + while (bytes_read > 0) { + iter->gap_start = bytes_read; + iter->element_count = bytes_read; + iter->next = new Page(); + iter->next->prev = iter; + iter = iter->next; + bytes_read = read(file, iter->elements, PAGE_SIZE); + } + if (iter->element_count == 0) { + delete iter; + } + close(file); + } + + void write_file(const char *pathname) { + int file = open(pathname, O_WRONLY | O_CREAT, S_IRUSR | S_IWUSR | S_IRGRP | S_IROTH); + Page *iter = storage; + while (iter) { + write(file, iter->elements, iter->gap_start); + write(file, iter->elements + iter->gap_end, PAGE_SIZE - iter->gap_end); + iter = iter->next; + } + close(file); + } +}; |