diff options
| author | Jiri Slaby <jslaby@suse.cz> | 2020-08-18 11:57:05 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2020-08-18 14:45:22 +0300 |
| commit | b1c32fcfadf5593ab7a63261cc8a5747c36e627e (patch) | |
| tree | 2b1b8c9a33b1cb3c8307ae4aedf2eaf2c6348de6 /drivers/tty | |
| parent | 6a6b76cc44c98a39d3e718aa2056e2e12b609615 (diff) | |
| download | linux-b1c32fcfadf5593ab7a63261cc8a5747c36e627e.tar.xz | |
vc_screen: extract vcs_read_buf_header
The attribute header handling is terrible in vcs_read_buf. Separate it
to a new function and simply do memmove (of up to 4 bytes) to the start
of the con_buf -- if user seeked.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200818085706.12163-15-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/tty')
| -rw-r--r-- | drivers/tty/vt/vc_screen.c | 31 |
1 files changed, 18 insertions, 13 deletions
diff --git a/drivers/tty/vt/vc_screen.c b/drivers/tty/vt/vc_screen.c index c178a1611223..9d68c6b36ddf 100644 --- a/drivers/tty/vt/vc_screen.c +++ b/drivers/tty/vt/vc_screen.c @@ -297,6 +297,22 @@ static void vcs_read_buf_noattr(const struct vc_data *vc, char *con_buf, } } +static unsigned int vcs_read_buf_header(const struct vc_data *vc, char *con_buf, + unsigned int pos, unsigned int count) +{ + count = min(HEADER_SIZE - pos, count); + + /* clamp header values if they don't fit */ + con_buf[0] = min(vc->vc_rows, 0xFFu); + con_buf[1] = min(vc->vc_cols, 0xFFu); + getconsxy(vc, con_buf + 2); + + if (pos) + memmove(con_buf, con_buf + pos, count); + + return count; +} + static unsigned int vcs_read_buf(const struct vc_data *vc, char *con_buf, unsigned int pos, unsigned int count, bool viewed, unsigned int *skip) @@ -306,22 +322,11 @@ static unsigned int vcs_read_buf(const struct vc_data *vc, char *con_buf, unsigned int filled = count; if (pos < HEADER_SIZE) { - /* clamp header values if they don't fit */ - con_buf[0] = min(vc->vc_rows, 0xFFu); - con_buf[1] = min(vc->vc_cols, 0xFFu); - getconsxy(vc, con_buf + 2); - - *skip += pos; - count += pos; - if (count > CON_BUF_SIZE) { - count = CON_BUF_SIZE; - filled = count - pos; - } + count -= vcs_read_buf_header(vc, con_buf, pos, count); - /* Advance state pointers and move on. */ - count -= min(HEADER_SIZE, count); pos = HEADER_SIZE; con_buf += HEADER_SIZE; + /* If count >= 0, then pos is even... */ } else if (pos & 1) { /* |