[DTrace-devel] [PATCH 03/47] Remove obsolete dt_fd, dt_ftfd, and dt_fterr

[Kris Van Hees]

Given that DTrace no longer makes use of the ioctl() interface to a
DTrace kernel component  we can remove all references to these members
in dtrace_hdl_t.  We retain dtrace_ctlfd() because it is part of the
public API, and dt_ioctl() because various parts of libdtrace still
need to rewritten to replace the ioctl() use.

Orabug: 31220516
Signed-off-by: Kris Van Hees <kris.van.hees at oracle.com>
---
 libdtrace/dt_impl.h |  3 ---
 libdtrace/dt_open.c | 13 ++++++-------
 libdtrace/dt_pid.c  | 27 +++------------------------
 libdtrace/dt_subr.c | 14 ++++++--------
 4 files changed, 15 insertions(+), 42 deletions(-)

diff --git a/libdtrace/dt_impl.h b/libdtrace/dt_impl.h
index 0630dd4c..62a9b0a9 100644
--- a/libdtrace/dt_impl.h
+++ b/libdtrace/dt_impl.h
@@ -330,9 +330,6 @@ struct dtrace_hdl {
 	int dt_version;		/* library version requested by client */
 	int dt_ctferr;		/* error resulting from last CTF failure */
 	int dt_errno;		/* error resulting from last failed operation */
-	int dt_fd;		/* file descriptor for dtrace pseudo-device */
-	int dt_ftfd;		/* file descriptor for fasttrap pseudo-device */
-	int dt_fterr;		/* saved errno from failed open of dt_ftfd */
 	int dt_cdefs_fd;	/* file descriptor for C CTF debugging cache */
 	int dt_ddefs_fd;	/* file descriptor for D CTF debugging cache */
 	int dt_stdout_fd;	/* file descriptor for saved stdout */
diff --git a/libdtrace/dt_open.c b/libdtrace/dt_open.c
index ce8e71a1..6b0ba71d 100644
--- a/libdtrace/dt_open.c
+++ b/libdtrace/dt_open.c
@@ -710,8 +710,6 @@ dt_vopen(int version, int flags, int *errp,
 	dtp->dt_xlatemode = DT_XL_STATIC;
 	dtp->dt_stdcmode = DT_STDC_XA;
 	dtp->dt_version = version;
-	dtp->dt_fd = -1;		/* FIXME: will be removed later */
-	dtp->dt_ftfd = -1;		/* FIXME: will be removed later */
 	dtp->dt_cdefs_fd = -1;
 	dtp->dt_ddefs_fd = -1;
 	dtp->dt_stdout_fd = -1;
@@ -1190,10 +1188,6 @@ dtrace_close(dtrace_hdl_t *dtp)
 
 	dt_pcap_destroy(dtp);
 
-	if (dtp->dt_fd != -1)
-		close(dtp->dt_fd);
-	if (dtp->dt_ftfd != -1)
-		close(dtp->dt_ftfd);
 	if (dtp->dt_cdefs_fd != -1)
 		close(dtp->dt_cdefs_fd);
 	if (dtp->dt_ddefs_fd != -1)
@@ -1240,8 +1234,13 @@ dtrace_close(dtrace_hdl_t *dtp)
 	dt_debug_dump(0);
 }
 
+/*
+ * DTrace no longer uses an ioctl() interface to communicate with a DTrace
+ * kernel component.  We retain this function because it is part of the
+ * libdtrace API.
+ */
 int
 dtrace_ctlfd(dtrace_hdl_t *dtp)
 {
-	return (dtp->dt_fd);
+	return -1;
 }
diff --git a/libdtrace/dt_pid.c b/libdtrace/dt_pid.c
index 3e331a5a..2d6e3a7c 100644
--- a/libdtrace/dt_pid.c
+++ b/libdtrace/dt_pid.c
@@ -101,11 +101,7 @@ dt_pid_create_fbt_probe(struct ps_prochandle *P, dtrace_hdl_t *dtp,
 	ftp->ftps_glen = 0;		/* no glob pattern */
 	ftp->ftps_gstr[0] = '\0';
 
-	if (ioctl(dtp->dt_ftfd, FASTTRAPIOC_MAKEPROBE, ftp) != 0) {
-		dt_dprintf("fasttrap probe creation ioctl failed: %s\n",
-		    strerror(errno));
-		return (dt_set_errno(dtp, errno));
-	}
+	/* Create a probe using 'ftp'. */
 
 	return (1);
 }
@@ -121,11 +117,7 @@ dt_pid_create_glob_offset_probes(struct ps_prochandle *P, dtrace_hdl_t *dtp,
 
 	strncpy(ftp->ftps_gstr, pattern, ftp->ftps_glen + 1);
 
-	if (ioctl(dtp->dt_ftfd, FASTTRAPIOC_MAKEPROBE, ftp) != 0) {
-		dt_dprintf("fasttrap probe creation ioctl failed: %s\n",
-		    strerror(errno));
-		return (dt_set_errno(dtp, errno));
-	}
+	/* Create a probe using 'ftp'. */
 
 	return (1);
 }
@@ -699,20 +691,7 @@ dt_pid_create_probes(dtrace_probedesc_t *pdp, dtrace_hdl_t *dtp, dt_pcb_t *pcb)
 	if ((pid = dt_pid_get_pid(pdp, dtp, pcb, NULL)) == -1)
 		return (-1);
 
-	if (dtp->dt_ftfd == -1) {
-		if (dtp->dt_fterr == ENOENT) {
-			(void) dt_pid_error(dtp, pcb, NULL, NULL, D_PROC_NODEV,
-			    "pid provider is not installed on this system");
-		} else {
-			(void) dt_pid_error(dtp, pcb, NULL, NULL, D_PROC_NODEV,
-			    "pid provider is not available: %s",
-			    strerror(dtp->dt_fterr));
-		}
-
-		return (-1);
-	}
-
-	(void) snprintf(provname, sizeof (provname), "pid%d", (int)pid);
+	snprintf(provname, sizeof (provname), "pid%d", (int)pid);
 
 	if (gmatch(provname, pdp->prv) != 0) {
 		pid = dt_proc_grab_lock(dtp, pid, DTRACE_PROC_WAITING);
diff --git a/libdtrace/dt_subr.c b/libdtrace/dt_subr.c
index 8610e47d..14824578 100644
--- a/libdtrace/dt_subr.c
+++ b/libdtrace/dt_subr.c
@@ -447,17 +447,15 @@ dt_cpp_pop_arg(dtrace_hdl_t *dtp)
 	return (arg);
 }
 
+/*
+ * This function will be removed in the near future because we no longer use
+ * the DTrace ioctl() interface.  It is retained for now while other code in
+ * libdtrace is being rewritten.  Any calls to this function will result in an
+ * error.
+ */
 int
 dt_ioctl(dtrace_hdl_t *dtp, unsigned long int val, void *arg)
 {
-	const dtrace_vector_t *v = dtp->dt_vector;
-
-	if (v != NULL)
-		return (v->dtv_ioctl(dtp->dt_varg, val, arg));
-
-	if (dtp->dt_fd >= 0)
-		return (ioctl(dtp->dt_fd, val, arg));
-
 	errno = EBADF;
 	return (-1);
 }
-- 
2.26.0