MINOR: cli: add a new "show fd" command
This one dumps the fdtab for all active FDs with some quickly interpretable
characters to read the flags (like upper case=set, lower case=unset). It
can probably be improved to report fdupdt[] and/or fdinfo[] but at least it
provides a good start and allows to see how FDs are seen. When the fd owner
is a connection, its flags are also reported as it can help compare with the
polling status, and the target (fe/px/sv) as well. When it's a listener, the
listener's state is reported as well as the frontend it belongs to.
diff --git a/src/cli.c b/src/cli.c
index fef34e9..6498815 100644
--- a/src/cli.c
+++ b/src/cli.c
@@ -66,6 +66,7 @@
#include <proto/server.h>
#include <proto/stream_interface.h>
#include <proto/task.h>
+#include <proto/proto_udp.h>
static struct applet cli_applet;
@@ -734,6 +735,106 @@
return 1;
}
+/* This function dumps all file descriptors states (or the requested one) to
+ * the buffer. It returns 0 if the output buffer is full and it needs to be
+ * called again, otherwise non-zero. Dumps only one entry if st2 == STAT_ST_END.
+ * It uses cli.i0 as the fd number to restart from.
+ */
+static int cli_io_handler_show_fd(struct appctx *appctx)
+{
+ struct stream_interface *si = appctx->owner;
+ int fd = appctx->ctx.cli.i0;
+
+ if (unlikely(si_ic(si)->flags & (CF_WRITE_ERROR|CF_SHUTW)))
+ return 1;
+
+ chunk_reset(&trash);
+
+ /* we have two inner loops here, one for the proxy, the other one for
+ * the buffer.
+ */
+ while (fd < maxfd) {
+ struct fdtab fdt;
+ struct listener *li;
+ struct server *sv;
+ struct proxy *px;
+ uint32_t conn_flags;
+
+ fdt = fdtab[fd];
+
+ if (fdt.iocb == conn_fd_handler) {
+ conn_flags = ((struct connection *)fdt.owner)->flags;
+ li = objt_listener(((struct connection *)fdt.owner)->target);
+ sv = objt_server(((struct connection *)fdt.owner)->target);
+ px = objt_proxy(((struct connection *)fdt.owner)->target);
+ }
+ else if (fdt.iocb == listener_accept)
+ li = fdt.owner;
+
+ if (!fdt.owner)
+ goto skip; // closed
+
+ chunk_printf(&trash,
+ " %5d : st=0x%02x(R:%c%c%c W:%c%c%c) ev=0x%02x(%c%c%c%c%c) [%c%c%c%c] cache=%u owner=%p iocb=%p(%s)",
+ fd,
+ fdt.state,
+ (fdt.state & FD_EV_POLLED_R) ? 'P' : 'p',
+ (fdt.state & FD_EV_READY_R) ? 'R' : 'r',
+ (fdt.state & FD_EV_ACTIVE_R) ? 'A' : 'a',
+ (fdt.state & FD_EV_POLLED_W) ? 'P' : 'p',
+ (fdt.state & FD_EV_READY_W) ? 'R' : 'r',
+ (fdt.state & FD_EV_ACTIVE_W) ? 'A' : 'a',
+ fdt.ev,
+ (fdt.ev & FD_POLL_HUP) ? 'H' : 'h',
+ (fdt.ev & FD_POLL_ERR) ? 'E' : 'e',
+ (fdt.ev & FD_POLL_OUT) ? 'O' : 'o',
+ (fdt.ev & FD_POLL_PRI) ? 'P' : 'p',
+ (fdt.ev & FD_POLL_IN) ? 'I' : 'i',
+ fdt.new ? 'N' : 'n',
+ fdt.updated ? 'U' : 'u',
+ fdt.linger_risk ? 'L' : 'l',
+ fdt.cloned ? 'C' : 'c',
+ fdt.cache,
+ fdt.owner,
+ fdt.iocb,
+ (fdt.iocb == conn_fd_handler) ? "conn_fd_handler" :
+ (fdt.iocb == dgram_fd_handler) ? "dgram_fd_handler" :
+ (fdt.iocb == listener_accept) ? "listener_accept" :
+ "unknown");
+
+ if (fdt.iocb == conn_fd_handler) {
+ chunk_appendf(&trash, " cflg=0x%08x", conn_flags);
+ if (px)
+ chunk_appendf(&trash, " px=%s", px->id);
+ else if (sv)
+ chunk_appendf(&trash, " sv=%s/%s", sv->id, sv->proxy->id);
+ else if (li)
+ chunk_appendf(&trash, " fe=%s", li->bind_conf->frontend->id);
+ }
+ else if (fdt.iocb == listener_accept) {
+ chunk_appendf(&trash, " l.st=%s fe=%s",
+ listener_state_str(li),
+ li->bind_conf->frontend->id);
+ }
+
+ chunk_appendf(&trash, "\n");
+
+ if (bi_putchk(si_ic(si), &trash) == -1) {
+ si_applet_cant_put(si);
+ return 0;
+ }
+ skip:
+ if (appctx->st2 == STAT_ST_END)
+ break;
+
+ fd++;
+ appctx->ctx.cli.i0 = fd;
+ }
+
+ /* dump complete */
+ return 1;
+}
+
/*
* CLI IO handler for `show cli sockets`.
* Uses ctx.cli.p0 to store the restart pointer.
@@ -863,6 +964,24 @@
return 0;
}
+/* parse a "show fd" CLI request. Returns 0 if it needs to continue, 1 if it
+ * wants to stop here. It puts the FD number into cli.i0 if a specific FD is
+ * requested and sets st2 to STAT_ST_END, otherwise leaves 0 in i0.
+ */
+static int cli_parse_show_fd(char **args, struct appctx *appctx, void *private)
+{
+ if (!cli_has_level(appctx, ACCESS_LVL_OPER))
+ return 1;
+
+ appctx->ctx.cli.i0 = 0;
+
+ if (*args[2]) {
+ appctx->ctx.cli.i0 = atoi(args[2]);
+ appctx->st2 = STAT_ST_END;
+ }
+ return 0;
+}
+
/* parse a "set timeout" CLI request. It always returns 1. */
static int cli_parse_set_timeout(char **args, struct appctx *appctx, void *private)
{
@@ -1234,6 +1353,7 @@
{ { "set", "timeout", NULL }, "set timeout : change a timeout setting", cli_parse_set_timeout, NULL, NULL },
{ { "show", "env", NULL }, "show env [var] : dump environment variables known to the process", cli_parse_show_env, cli_io_handler_show_env, NULL },
{ { "show", "cli", "sockets", NULL }, "show cli sockets : dump list of cli sockets", cli_parse_default, cli_io_handler_show_cli_sock, NULL },
+ { { "show", "fd", NULL }, "show fd [num] : dump list of file descriptors in use", cli_parse_show_fd, cli_io_handler_show_fd, NULL },
{ { "_getsocks", NULL }, NULL, _getsocks, NULL },
{{},}
}};