Add a tty code to indicate a resize frame. The body contains two big endian 16-bit integers rows and columns.
After reset, the guest must be informed of the terminal size again. A chardev that doesn't report its size yields 0x0, which shouldn't replace the guest's default. Signed-off-by: Maximilian Immanuel Brandtner <[email protected]> --- Changelog: v2: - Use packed struct and named event type codes for resize frames - Trigger initial resize event in console_reset() instead of console_init(), skip when chardev reports no size - Reset event_pending after resize event Requires the following pre-req: [PATCH v7 00/12] virtio-console: notify about the terminal size (https://lore.kernel.org/qemu-devel/[email protected]/) Testing: - Tested on QEMU: commit 38879a667f with the following patches applied: [PATCH v7 00/12] virtio-console: notify about the terminal size - Tested on linux-next (commit c1f49dea2b8f) with the following patches applied: [PATCH 0/2] s390/sclp: Resize for sclp-vt220 console --- hw/char/sclpconsole.c | 92 +++++++++++++++++++++++++++++++++++++------ 1 file changed, 80 insertions(+), 12 deletions(-) diff --git a/hw/char/sclpconsole.c b/hw/char/sclpconsole.c index 179d12745c..12033e1e46 100644 --- a/hw/char/sclpconsole.c +++ b/hw/char/sclpconsole.c @@ -33,6 +33,9 @@ typedef struct ASCIIConsoleData { /* max size for ASCII data in 4K SCCB page */ #define SIZE_BUFFER_VT220 4080 +#define SCLP_CONSOLE_EVENT_TYPE_DATA 0x00 +#define SCLP_CONSOLE_EVENT_TYPE_RESIZE 0x08 + struct SCLPConsole { SCLPEvent event; CharFrontend chr; @@ -42,6 +45,8 @@ struct SCLPConsole { uint32_t iov_data_len; /* length of byte stream in buffer */ uint32_t iov_sclp_rest; /* length of byte stream not read via SCLP */ bool notify; /* qemu_notify_event() req'd if true */ + bool resize; + bool resize_init; }; typedef struct SCLPConsole SCLPConsole; @@ -49,6 +54,12 @@ typedef struct SCLPConsole SCLPConsole; DECLARE_INSTANCE_CHECKER(SCLPConsole, SCLP_CONSOLE, TYPE_SCLP_CONSOLE) +typedef struct SCLPConsoleResizeData { + uint8_t type; + uint16_t rows; + uint16_t cols; +} QEMU_PACKED SCLPConsoleResizeData; + /* character layer call-back functions */ /* Return number of bytes that fit into iov buffer */ @@ -81,6 +92,29 @@ static void chr_read(void *opaque, const uint8_t *buf, int size) sclp_service_interrupt(0); } +static void chr_event(void *opaque, QEMUChrEvent event) +{ + SCLPConsole *scon = opaque; + + assert(scon); + + switch (event) { + case CHR_EVENT_RESIZE: + case CHR_EVENT_MUX_IN: + scon->resize = true; + scon->resize_init = false; + scon->event.event_pending = true; + sclp_service_interrupt(0); + break; + case CHR_EVENT_BREAK: + case CHR_EVENT_OPENED: + case CHR_EVENT_MUX_OUT: + case CHR_EVENT_CLOSED: + /* ignore */ + break; + } +} + /* functions to be called by event facility */ static bool can_handle_event(uint8_t type) @@ -104,10 +138,37 @@ static sccb_mask_t receive_mask(void) static void get_console_data(SCLPEvent *event, uint8_t *buf, size_t *size, int avail) { + SCLPConsoleResizeData resize_data; SCLPConsole *cons = SCLP_CONSOLE(event); + uint16_t rows, cols; + + if (cons->resize) { + if (avail < sizeof(resize_data)) { + *size = 0; + return; + } - /* first byte is hex 0 saying an ascii string follows */ - *buf++ = '\0'; + qemu_chr_fe_get_winsize(&cons->chr, &cols, &rows); + + if (cons->resize_init && cols == 0 && rows == 0) { + *size = 0; + } else { + resize_data.type = SCLP_CONSOLE_EVENT_TYPE_RESIZE; + resize_data.rows = cpu_to_be16(rows); + resize_data.cols = cpu_to_be16(cols); + + memcpy(buf, &resize_data, sizeof(resize_data)); + *size = sizeof(resize_data); + } + + cons->resize = false; + cons->resize_init = false; + event->event_pending = cons->iov_sclp_rest != 0; + + return; + } + + *buf++ = SCLP_CONSOLE_EVENT_TYPE_DATA; avail--; /* if all data fit into provided SCLP buffer */ if (avail >= cons->iov_sclp_rest) { @@ -150,6 +211,9 @@ static int read_event_data(SCLPEvent *event, EventBufferHeader *evt_buf_hdr, to = (uint8_t *)&acd->data; avail = *slen - sizeof(ASCIIConsoleData); get_console_data(event, to, &src_len, avail); + if (src_len == 0) { + return 0; + } acd->ebh.length = cpu_to_be16(sizeof(ASCIIConsoleData) + src_len); acd->ebh.type = SCLP_EVENT_ASCII_CONSOLE_DATA; @@ -233,22 +297,26 @@ static int console_init(SCLPEvent *event) } console_available = true; qemu_chr_fe_set_handlers(&scon->chr, chr_can_read, - chr_read, NULL, NULL, scon, NULL, true); + chr_read, chr_event, NULL, scon, NULL, true); return 0; } static void console_reset(DeviceState *dev) { - SCLPEvent *event = SCLP_EVENT(dev); - SCLPConsole *scon = SCLP_CONSOLE(event); - - event->event_pending = false; - scon->iov_sclp = 0; - scon->iov_bs = 0; - scon->iov_data_len = 0; - scon->iov_sclp_rest = 0; - scon->notify = false; + SCLPEvent *event = SCLP_EVENT(dev); + SCLPConsole *scon = SCLP_CONSOLE(event); + + scon->iov_sclp = 0; + scon->iov_bs = 0; + scon->iov_data_len = 0; + scon->iov_sclp_rest = 0; + scon->notify = false; + + /* the guest defaults its terminal size on reset, announce the real one */ + scon->resize = true; + scon->resize_init = true; + event->event_pending = true; } static const Property console_properties[] = { -- 2.54.0
