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rename wbuffer, limit max size
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@stek29
stek29 committed Aug 6, 2019
1 parent a871ff1 commit 6b6a700
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Showing 2 changed files with 61 additions and 49 deletions.
100 changes: 56 additions & 44 deletions app/Pasteboard.m
View file
Original file line number Diff line number Diff line change
Expand Up @@ -14,7 +14,9 @@
#define fd_priv(fd) fd->clipboard
typedef struct fd clip_fd;

#define INITIAL_WBUFFER_SIZE 1024
#define INITIAL_BUFFER_CAP 1024
// 8MB: https://stackoverflow.com/a/3523175
#define MAXIMAL_BUFFER_CAP 8*1024*1024

// If pasteboard contents were changed since file was opened,
// all read operations on in return error
Expand All @@ -34,9 +36,9 @@ static int check_read_generation(clip_fd *fd) {
}

static const char *get_data(clip_fd *fd, size_t *len) {
if (fd_priv(fd).wbuffer != NULL) {
*len = fd_priv(fd).wbuffer_len;
return fd_priv(fd).wbuffer;
if (fd_priv(fd).buffer != NULL) {
*len = fd_priv(fd).buffer_len;
return fd_priv(fd).buffer;
}

if (check_read_generation(fd) != 0) {
Expand All @@ -48,14 +50,40 @@ static int check_read_generation(clip_fd *fd) {
return contents.UTF8String;
}

// wbuffer => UIPasteboard
static int realloc_to_fit(clip_fd* fd, size_t fit_len) {
// (Re)allocate buffer if there's not enough space to fit fit_len
if (fit_len <= fd_priv(fd).buffer_cap) {
return 0;
}
if (fit_len > MAXIMAL_BUFFER_CAP) {
return 1;
}

size_t size = fd_priv(fd).buffer_cap * 2;
if (size == 0) {
size = INITIAL_BUFFER_CAP;
}
while (size < fit_len) size *= 2;

void *new_buf = realloc(fd_priv(fd).buffer, size);
if (new_buf == NULL) {
return 1;
}

fd_priv(fd).buffer = new_buf;
fd_priv(fd).buffer_cap = size;

return 0;
}

// buffer => UIPasteboard
static int clipboard_wsync(clip_fd *fd) {
if (fd_priv(fd).wbuffer == NULL) {
if (fd_priv(fd).buffer == NULL) {
return 0;
}

void *data = fd_priv(fd).wbuffer;
size_t len = fd_priv(fd).wbuffer_len;
void *data = fd_priv(fd).buffer;
size_t len = fd_priv(fd).buffer_len;

// FIXME(stek29): This logs "Returning local object of class NSString"
// and I have no idea why (or how to fix it)
Expand All @@ -71,31 +99,25 @@ static int clipboard_wsync(clip_fd *fd) {
return 0;
}

// UIPasteboard => wbuffer, return len
// UIPasteboard => buffer, return len
static ssize_t clipboard_rsync(clip_fd *fd) {
if (fd_priv(fd).wbuffer != NULL) {
free(fd_priv(fd).wbuffer);
fd_priv(fd).wbuffer = NULL;
fd_priv(fd).wbuffer_size = 0;
fd_priv(fd).wbuffer_len = 0;
if (fd_priv(fd).buffer != NULL) {
free(fd_priv(fd).buffer);
fd_priv(fd).buffer = NULL;
fd_priv(fd).buffer_cap = 0;
fd_priv(fd).buffer_len = 0;
}

size_t len;
const void *data = get_data(fd, &len);
size_t size = INITIAL_WBUFFER_SIZE;

// Make sure size is still INITIAL_WBUFFER_SIZE based
while (size < len) size *= 2;

void *wbuffer = malloc(size);
if (wbuffer == NULL) {

// Make sure size is still INITIAL_BUFFER_CAP based
if (realloc_to_fit(fd, len)) {
return _ENOMEM;
}
memcpy(wbuffer, data, len);

fd_priv(fd).wbuffer = wbuffer;
fd_priv(fd).wbuffer_len = len;
fd_priv(fd).wbuffer_size = size;
memcpy(fd_priv(fd).buffer, data, len);
fd_priv(fd).buffer_len = len;

return len;
}
Expand Down Expand Up @@ -137,30 +159,20 @@ static ssize_t clipboard_read(clip_fd *fd, void *buf, size_t bufsize) {

static ssize_t clipboard_write(clip_fd *fd, const void *buf, size_t bufsize) {
size_t new_len = fd->offset + bufsize;
size_t old_len = fd_priv(fd).wbuffer_len;
size_t old_len = fd_priv(fd).buffer_len;

// (Re)allocate wbuffer if there's not enough space to fit new_len
if (new_len > fd_priv(fd).wbuffer_size) {
size_t new_size = fd_priv(fd).wbuffer_size * 2;
if (new_size == 0) {
new_size = INITIAL_WBUFFER_SIZE;
}
void *new_buf = realloc(fd_priv(fd).wbuffer, new_size);
if (new_buf == NULL) {
return _ENOMEM;
}
fd_priv(fd).wbuffer = new_buf;
fd_priv(fd).wbuffer_size = new_size;
if (realloc_to_fit(fd, new_len)) {
return _ENOMEM;
}

// fill the hole between new offset and old len
if (old_len < fd->offset) {
memset(fd_priv(fd).wbuffer + old_len, '\0', fd->offset - old_len);
memset(fd_priv(fd).buffer + old_len, '\0', fd->offset - old_len);
}

memcpy(fd_priv(fd).wbuffer + fd->offset, buf, bufsize);
memcpy(fd_priv(fd).buffer + fd->offset, buf, bufsize);
fd->offset += bufsize;
fd_priv(fd).wbuffer_len = new_len;
fd_priv(fd).buffer_len = new_len;

return bufsize;
}
Expand Down Expand Up @@ -202,8 +214,8 @@ static off_t_ clipboard_lseek(clip_fd *fd, off_t_ off, int whence) {

static int clipboard_close(clip_fd *fd) {
clipboard_wsync(fd);
if (fd_priv(fd).wbuffer != NULL) {
free(fd_priv(fd).wbuffer);
if (fd_priv(fd).buffer != NULL) {
free(fd_priv(fd).buffer);
}
return 0;
}
Expand All @@ -212,7 +224,7 @@ static int clipboard_open(int major, int minor, clip_fd *fd) {
// Zero fd_priv data
memset(&fd_priv(fd), 0, sizeof(fd_priv(fd)));

// If O_APPEND_ is set, initialize wbuffer with current pasteboard contents
// If O_APPEND_ is set, initialize buffer with current pasteboard contents
if (fd->flags & O_APPEND_) {
ssize_t len = clipboard_rsync(fd);
if (len < 0) {
Expand Down
10 changes: 5 additions & 5 deletions fs/fd.h
View file
Original file line number Diff line number Diff line change
Expand Up @@ -60,12 +60,12 @@ struct fd {
struct {
// UIPasteboard.changeCount
uint64_t generation;
// Buffer
void* wbuffer;
// Buffer for written data
void* buffer;
// it's capacity
size_t wbuffer_size;
// length of data in the buffer
size_t wbuffer_len;
size_t buffer_cap;
// length of actual data stored in the buffer
size_t buffer_len;
} clipboard;
};
// fs data
Expand Down

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