6885 CTF Everywhere Part 1

6886 Want ctfdiff
6887 ctfdump should be written in terms of libctf
6888 ctfmerge should be implemented in terms of libctf
6889 ctfconvert should be implemented in terms of libctf
6890 Want general workq
6891 Want general mergeq
6892 ctf_add_encoded assigns() incorrect byte size to types
6893 ctf_add_{struct,union,enum} can reuse forwards
6894 ctf_add_{struct,union,enum} occasionally forget to dirty the ctf_file_t
6895 ctf_add_member could better handle bitfields
6896 ctf_type_size() reports wrong size for forwards
6897 Want libctf ctf_kind_name() function
6898 Want libctf function to set struct/union size
Portions contributed by: John Levon <john.levon@joyent.com>
Portions contributed by: Richard Lowe <richlowe@richlowe.net>
Reviewed by: John Levon <john.levon@joyent.com>
Reviewed by: Andy Fiddaman <andy@omniosce.org>
Reviewed by: Gergő Doma <domag02@gmail.com>
Approved by: Dan McDonald <danmcd@joyent.com>

1 files changed, 388 insertions, 0 deletions

diff --git a/usr/src/cmd/ctfconvert/ctfconvert.c b/usr/src/cmd/ctfconvert/ctfconvert.c
new file mode 100644
index 0000000000..3ff96c5089
--- /dev/null
+++ b/usr/src/cmd/ctfconvert/ctfconvert.c
@@ -0,0 +1,388 @@
+/*
+ * This file and its contents are supplied under the terms of the
+ * Common Development and Distribution License ("CDDL"), version 1.0.
+ * You may only use this file in accordance with the terms of version
+ * 1.0 of the CDDL.
+ *
+ * A full copy of the text of the CDDL should have accompanied this
+ * source.  A copy of the CDDL is also available via the Internet at
+ * http://www.illumos.org/license/CDDL.
+ */
+
+/*
+ * Copyright (c) 2015, Joyent, Inc.
+ */
+
+/*
+ * Create CTF from extant debugging information
+ */
+
+#include <stdio.h>
+#include <unistd.h>
+#include <stdlib.h>
+#include <stdarg.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <errno.h>
+#include <libelf.h>
+#include <libctf.h>
+#include <string.h>
+#include <libgen.h>
+#include <limits.h>
+#include <strings.h>
+#include <sys/debug.h>
+
+#define	CTFCONVERT_OK		0
+#define	CTFCONVERT_FATAL	1
+#define	CTFCONVERT_USAGE	2
+
+#define	CTFCONVERT_DEFAULT_NTHREADS	4
+
+#define	CTFCONVERT_ALTEXEC	"CTFCONVERT_ALTEXEC"
+
+static char *ctfconvert_progname;
+
+static void
+ctfconvert_fatal(const char *fmt, ...)
+{
+	va_list ap;
+
+	(void) fprintf(stderr, "%s: ", ctfconvert_progname);
+	va_start(ap, fmt);
+	(void) vfprintf(stderr, fmt, ap);
+	va_end(ap);
+
+	exit(CTFCONVERT_FATAL);
+}
+
+
+static void
+ctfconvert_usage(const char *fmt, ...)
+{
+	if (fmt != NULL) {
+		va_list ap;
+
+		(void) fprintf(stderr, "%s: ", ctfconvert_progname);
+		va_start(ap, fmt);
+		(void) vfprintf(stderr, fmt, ap);
+		va_end(ap);
+	}
+
+	(void) fprintf(stderr, "Usage: %s [-is] [-j nthrs] [-l label | "
+	    "-L labelenv] [-o outfile] input\n"
+	    "\n"
+	    "\t-i  ignore files not built partially from C sources\n"
+	    "\t-j  use nthrs threads to perform the merge\n"
+	    "\t-k  keep around original input file on failure\n"
+	    "\t-o  copy input to outfile and add CTF\n"
+	    "\t-l  set output container's label to specified value\n"
+	    "\t-L  set output container's label to value from environment\n",
+	    ctfconvert_progname);
+}
+
+/*
+ * This is a bit unfortunate. Traditionally we do type uniquification across all
+ * modules in the kernel, including ip and unix against genunix. However, when
+ * _MACHDEP is defined, then the cpu_t ends up having an additional member
+ * (cpu_m), thus changing the ability for us to uniquify against it. This in
+ * turn causes a lot of type sprawl, as there's a lot of things that end up
+ * referring to the cpu_t and it chains out from there.
+ *
+ * So, if we find that a cpu_t has been defined and it has a couple of useful
+ * sentinel members and it does *not* have the cpu_m member, then we will try
+ * and lookup or create a forward declaration to the machcpu, append it to the
+ * end, and update the file.
+ *
+ * This currently is only invoked if an undocumented option -X is passed. This
+ * value is private to illumos and it can be changed at any time inside of it,
+ * so if -X wants to be used for something, it should be. The ability to rely on
+ * -X for others is strictly not an interface in any way, shape, or form.
+ *
+ * The following struct contains most of the information that we care about and
+ * that we want to validate exists before we decide what to do.
+ */
+
+typedef struct ctfconvert_fixup {
+	boolean_t	cf_cyclic;	/* Do we have a cpu_cyclic member */
+	boolean_t	cf_mcpu;	/* We have a cpu_m member */
+	boolean_t	cf_lastpad;	/* Is the pad member the last entry */
+	ulong_t		cf_padoff;	/* offset of the pad */
+} ctfconvert_fixup_t;
+
+/* ARGSUSED */
+static int
+ctfconvert_fixup_genunix_cb(const char *name, ctf_id_t tid, ulong_t off,
+    void *arg)
+{
+	ctfconvert_fixup_t *cfp = arg;
+
+	cfp->cf_lastpad = B_FALSE;
+	if (strcmp(name, "cpu_cyclic") == 0) {
+		cfp->cf_cyclic = B_TRUE;
+		return (0);
+	}
+
+	if (strcmp(name, "cpu_m") == 0) {
+		cfp->cf_mcpu = B_TRUE;
+		return (0);
+	}
+
+	if (strcmp(name, "cpu_m_pad") == 0) {
+		cfp->cf_lastpad = B_TRUE;
+		cfp->cf_padoff = off;
+		return (0);
+	}
+
+	return (0);
+}
+
+static void
+ctfconvert_fixup_genunix(ctf_file_t *fp)
+{
+	ctf_id_t cpuid, mcpu;
+	ssize_t sz;
+	ctfconvert_fixup_t cf;
+	int model, ptrsz;
+
+	cpuid = ctf_lookup_by_name(fp, "struct cpu");
+	if (cpuid == CTF_ERR)
+		return;
+
+	if (ctf_type_kind(fp, cpuid) != CTF_K_STRUCT)
+		return;
+
+	if ((sz = ctf_type_size(fp, cpuid)) == CTF_ERR)
+		return;
+
+	model = ctf_getmodel(fp);
+	VERIFY(model == CTF_MODEL_ILP32 || model == CTF_MODEL_LP64);
+	ptrsz = model == CTF_MODEL_ILP32 ? 4 : 8;
+
+	bzero(&cf, sizeof (ctfconvert_fixup_t));
+	if (ctf_member_iter(fp, cpuid, ctfconvert_fixup_genunix_cb, &cf) ==
+	    CTF_ERR)
+		return;
+
+	/*
+	 * Finally, we want to verify that the cpu_m is actually the last member
+	 * that we have here.
+	 */
+	if (cf.cf_cyclic == B_FALSE || cf.cf_mcpu == B_TRUE ||
+	    cf.cf_lastpad == B_FALSE) {
+		return;
+	}
+
+	if (cf.cf_padoff + ptrsz * NBBY != sz * NBBY) {
+		return;
+	}
+
+	/*
+	 * Okay, we're going to do this, try to find a struct machcpu. We either
+	 * want a forward or a struct. If we find something else, error. If we
+	 * find nothing, add a forward and then add the member.
+	 */
+	mcpu = ctf_lookup_by_name(fp, "struct machcpu");
+	if (mcpu == CTF_ERR) {
+		mcpu = ctf_add_forward(fp, CTF_ADD_NONROOT, "machcpu",
+		    CTF_K_STRUCT);
+		if (mcpu == CTF_ERR) {
+			ctfconvert_fatal("failed to add 'struct machcpu' "
+			    "forward: %s", ctf_errmsg(ctf_errno(fp)));
+		}
+	} else {
+		int kind;
+		if ((kind = ctf_type_kind(fp, mcpu)) == CTF_ERR) {
+			ctfconvert_fatal("failed to get the type kind for "
+			    "the struct machcpu: %s",
+			    ctf_errmsg(ctf_errno(fp)));
+		}
+
+		if (kind != CTF_K_STRUCT && kind != CTF_K_FORWARD)
+			ctfconvert_fatal("encountered a struct machcpu of the "
+			    "wrong type, found type kind %d\n", kind);
+	}
+
+	if (ctf_update(fp) == CTF_ERR) {
+		ctfconvert_fatal("failed to update output file: %s\n",
+		    ctf_errmsg(ctf_errno(fp)));
+	}
+
+	if (ctf_add_member(fp, cpuid, "cpu_m", mcpu, sz * NBBY) == CTF_ERR) {
+		ctfconvert_fatal("failed to add the m_cpu member: %s\n",
+		    ctf_errmsg(ctf_errno(fp)));
+	}
+
+	if (ctf_update(fp) == CTF_ERR) {
+		ctfconvert_fatal("failed to update output file: %s\n",
+		    ctf_errmsg(ctf_errno(fp)));
+	}
+
+	VERIFY(ctf_type_size(fp, cpuid) == sz);
+}
+
+static void
+ctfconvert_altexec(char **argv)
+{
+	const char *alt;
+	char *altexec;
+
+	alt = getenv(CTFCONVERT_ALTEXEC);
+	if (alt == NULL || *alt == '\0')
+		return;
+
+	altexec = strdup(alt);
+	if (altexec == NULL)
+		ctfconvert_fatal("failed to allocate memory for altexec\n");
+	if (unsetenv(CTFCONVERT_ALTEXEC) != 0)
+		ctfconvert_fatal("failed to unset %s from environment: %s\n",
+		    CTFCONVERT_ALTEXEC, strerror(errno));
+
+	(void) execv(altexec, argv);
+	ctfconvert_fatal("failed to execute alternate program %s: %s",
+	    altexec, strerror(errno));
+}
+
+int
+main(int argc, char *argv[])
+{
+	int c, ifd, err;
+	boolean_t keep = B_FALSE;
+	uint_t flags = 0;
+	uint_t nthreads = CTFCONVERT_DEFAULT_NTHREADS;
+	const char *outfile = NULL;
+	const char *label = NULL;
+	const char *infile = NULL;
+	char *tmpfile;
+	ctf_file_t *ofp;
+	long argj;
+	char *eptr;
+	char buf[4096];
+	boolean_t optx = B_FALSE;
+
+	ctfconvert_progname = basename(argv[0]);
+
+	ctfconvert_altexec(argv);
+
+	while ((c = getopt(argc, argv, ":j:kl:L:o:iX")) != -1) {
+		switch (c) {
+		case 'k':
+			keep = B_TRUE;
+			break;
+		case 'l':
+			label = optarg;
+			break;
+		case 'L':
+			label = getenv(optarg);
+			break;
+		case 'j':
+			errno = 0;
+			argj = strtol(optarg, &eptr, 10);
+			if (errno != 0 || argj == LONG_MAX ||
+			    argj > 1024 || *eptr != '\0') {
+				ctfconvert_fatal("invalid argument for -j: "
+				    "%s\n", optarg);
+			}
+			nthreads = (uint_t)argj;
+			break;
+		case 'o':
+			outfile = optarg;
+			break;
+		case 'i':
+			flags |= CTF_CONVERT_F_IGNNONC;
+			break;
+		case 'X':
+			optx = B_TRUE;
+			break;
+		case ':':
+			ctfconvert_usage("Option -%c requires an operand\n",
+			    optopt);
+			return (CTFCONVERT_USAGE);
+		case '?':
+			ctfconvert_usage("Unknown option: -%c\n", optopt);
+			return (CTFCONVERT_USAGE);
+		}
+	}
+
+	argv += optind;
+	argc -= optind;
+
+	if (argc < 1) {
+		ctfconvert_usage("Missing required input file\n");
+		return (CTFCONVERT_USAGE);
+	}
+	infile = argv[0];
+
+	if (elf_version(EV_CURRENT) == EV_NONE)
+		ctfconvert_fatal("failed to initialize libelf: library is "
+		    "out of date\n");
+
+	ifd = open(infile, O_RDONLY);
+	if (ifd < 0) {
+		ctfconvert_fatal("failed to open input file %s: %s\n", infile,
+		    strerror(errno));
+	}
+
+	/*
+	 * By default we remove the input file on failure unless we've been
+	 * given an output file or -k has been specified.
+	 */
+	if (outfile != NULL && strcmp(infile, outfile) != 0)
+		keep = B_TRUE;
+
+	ofp = ctf_fdconvert(ifd, label, nthreads, flags, &err, buf,
+	    sizeof (buf));
+	if (ofp == NULL) {
+		/*
+		 * -i says that we shouldn't concern ourselves with source files
+		 * that weren't built from C source code in part. Because this
+		 * has been traditionally used across all of illumos, we still
+		 * honor it.
+		 */
+		if ((flags & CTF_CONVERT_F_IGNNONC) != 0 &&
+		    err == ECTF_CONVNOCSRC) {
+			exit(CTFCONVERT_OK);
+		}
+		if (keep == B_FALSE)
+			(void) unlink(infile);
+		ctfconvert_fatal("CTF conversion failed: %s\n",
+		    err == ECTF_CONVBKERR ? buf : ctf_errmsg(err));
+	}
+
+	if (optx == B_TRUE)
+		ctfconvert_fixup_genunix(ofp);
+
+	tmpfile = NULL;
+	if (outfile == NULL || strcmp(infile, outfile) == 0) {
+		if (asprintf(&tmpfile, "%s.ctf", infile) == -1) {
+			if (keep == B_FALSE)
+				(void) unlink(infile);
+			ctfconvert_fatal("failed to allocate memory for "
+			    "temporary file: %s\n", strerror(errno));
+		}
+		outfile = tmpfile;
+	}
+	err = ctf_elfwrite(ofp, infile, outfile, CTF_ELFWRITE_F_COMPRESS);
+	if (err == CTF_ERR) {
+		(void) unlink(outfile);
+		if (keep == B_FALSE)
+			(void) unlink(infile);
+		ctfconvert_fatal("failed to write CTF section to output file: "
+		    "%s", ctf_errmsg(ctf_errno(ofp)));
+	}
+	ctf_close(ofp);
+
+	if (tmpfile != NULL) {
+		if (rename(tmpfile, infile) != 0) {
+			int e = errno;
+			(void) unlink(outfile);
+			if (keep == B_FALSE)
+				(void) unlink(infile);
+			ctfconvert_fatal("failed to rename temporary file: "
+			    "%s\n", strerror(e));
+		}
+	}
+	free(tmpfile);
+
+	return (CTFCONVERT_OK);
+}