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, 210 insertions, 0 deletions

diff --git a/usr/src/lib/libctf/common/ctf_convert.c b/usr/src/lib/libctf/common/ctf_convert.c
new file mode 100644
index 0000000000..cbb4d48c76
--- /dev/null
+++ b/usr/src/lib/libctf/common/ctf_convert.c
@@ -0,0 +1,210 @@
+/*
+ * 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 2015 Joyent, Inc.
+ */
+
+/*
+ * Main conversion entry points. This has been designed such that there can be
+ * any number of different conversion backends. Currently we only have one that
+ * understands DWARFv2 (and bits of DWARFv4). Each backend should be placed in
+ * the ctf_converters list and each will be tried in turn.
+ */
+
+#include <libctf_impl.h>
+#include <gelf.h>
+
+ctf_convert_f ctf_converters[] = {
+	ctf_dwarf_convert
+};
+
+#define	NCONVERTS	(sizeof (ctf_converters) / sizeof (ctf_convert_f))
+
+typedef enum ctf_convert_source {
+	CTFCONV_SOURCE_NONE = 0x0,
+	CTFCONV_SOURCE_UNKNOWN = 0x01,
+	CTFCONV_SOURCE_C = 0x02,
+	CTFCONV_SOURCE_S = 0x04
+} ctf_convert_source_t;
+
+static void
+ctf_convert_ftypes(Elf *elf, ctf_convert_source_t *types)
+{
+	int i;
+	Elf_Scn *scn = NULL, *strscn;
+	*types = CTFCONV_SOURCE_NONE;
+	GElf_Shdr shdr;
+	Elf_Data *data, *strdata;
+
+	while ((scn = elf_nextscn(elf, scn)) != NULL) {
+
+		if (gelf_getshdr(scn, &shdr) == NULL)
+			return;
+
+		if (shdr.sh_type == SHT_SYMTAB)
+			break;
+	}
+
+	if (scn == NULL)
+		return;
+
+	if ((strscn = elf_getscn(elf, shdr.sh_link)) == NULL)
+		return;
+
+	if ((data = elf_getdata(scn, NULL)) == NULL)
+		return;
+
+	if ((strdata = elf_getdata(strscn, NULL)) == NULL)
+		return;
+
+	for (i = 0; i < shdr.sh_size / shdr.sh_entsize; i++) {
+		GElf_Sym sym;
+		const char *file;
+		size_t len;
+
+		if (gelf_getsym(data, i, &sym) == NULL)
+			return;
+
+		if (GELF_ST_TYPE(sym.st_info) != STT_FILE)
+			continue;
+
+		file = (const char *)((uintptr_t)strdata->d_buf + sym.st_name);
+		len = strlen(file);
+		if (len < 2 || file[len - 2] != '.') {
+			*types |= CTFCONV_SOURCE_UNKNOWN;
+			continue;
+		}
+
+		switch (file[len - 1]) {
+		case 'c':
+			*types |= CTFCONV_SOURCE_C;
+			break;
+		case 'h':
+			/* We traditionally ignore header files... */
+			break;
+		case 's':
+			*types |= CTFCONV_SOURCE_S;
+			break;
+		default:
+			*types |= CTFCONV_SOURCE_UNKNOWN;
+			break;
+		}
+	}
+}
+
+static ctf_file_t *
+ctf_elfconvert(int fd, Elf *elf, const char *label, uint_t nthrs, uint_t flags,
+    int *errp, char *errbuf, size_t errlen)
+{
+	int err, i;
+	ctf_file_t *fp = NULL;
+	boolean_t notsup = B_TRUE;
+	ctf_convert_source_t type;
+
+	if (errp == NULL)
+		errp = &err;
+
+	if (elf == NULL) {
+		*errp = EINVAL;
+		return (NULL);
+	}
+
+	if (flags & ~CTF_CONVERT_F_IGNNONC) {
+		*errp = EINVAL;
+		return (NULL);
+	}
+
+	if (elf_kind(elf) != ELF_K_ELF) {
+		*errp = ECTF_FMT;
+		return (NULL);
+	}
+
+	ctf_convert_ftypes(elf, &type);
+	ctf_dprintf("got types: %d\n", type);
+	if (flags & CTF_CONVERT_F_IGNNONC) {
+		if (type == CTFCONV_SOURCE_NONE ||
+		    (type & CTFCONV_SOURCE_UNKNOWN)) {
+			*errp = ECTF_CONVNOCSRC;
+			return (NULL);
+		}
+	}
+
+	for (i = 0; i < NCONVERTS; i++) {
+		ctf_conv_status_t cs;
+
+		fp = NULL;
+		cs = ctf_converters[i](fd, elf, nthrs, errp, &fp, errbuf,
+		    errlen);
+		if (cs == CTF_CONV_SUCCESS) {
+			notsup = B_FALSE;
+			break;
+		}
+		if (cs == CTF_CONV_ERROR) {
+			fp = NULL;
+			notsup = B_FALSE;
+			break;
+		}
+	}
+
+	if (notsup == B_TRUE) {
+		if ((flags & CTF_CONVERT_F_IGNNONC) != 0 &&
+		    (type & CTFCONV_SOURCE_C) == 0) {
+			*errp = ECTF_CONVNOCSRC;
+			return (NULL);
+		}
+		*errp = ECTF_NOCONVBKEND;
+		return (NULL);
+	}
+
+	/*
+	 * Succsesful conversion.
+	 */
+	if (fp != NULL) {
+		if (label == NULL)
+			label = "";
+		if (ctf_add_label(fp, label, fp->ctf_typemax, 0) == CTF_ERR) {
+			*errp = ctf_errno(fp);
+			ctf_close(fp);
+			return (NULL);
+		}
+		if (ctf_update(fp) == CTF_ERR) {
+			*errp = ctf_errno(fp);
+			ctf_close(fp);
+			return (NULL);
+		}
+	}
+
+	return (fp);
+}
+
+ctf_file_t *
+ctf_fdconvert(int fd, const char *label, uint_t nthrs, uint_t flags, int *errp,
+    char *errbuf, size_t errlen)
+{
+	int err;
+	Elf *elf;
+	ctf_file_t *fp;
+
+	if (errp == NULL)
+		errp = &err;
+
+	elf = elf_begin(fd, ELF_C_READ, NULL);
+	if (elf == NULL) {
+		*errp = ECTF_FMT;
+		return (NULL);
+	}
+
+	fp = ctf_elfconvert(fd, elf, label, nthrs, flags, errp, errbuf, errlen);
+
+	(void) elf_end(elf);
+	return (fp);
+}