1 files changed, 383 insertions, 0 deletions
diff --git a/tools/perf/util/symbol-minimal.c b/tools/perf/util/symbol-minimal.c
new file mode 100644
index 000000000..7119df77d
--- /dev/null
+++ b/tools/perf/util/symbol-minimal.c
@@ -0,0 +1,383 @@
+// SPDX-License-Identifier: GPL-2.0
+#include "symbol.h"
+#include "util.h"
+
+#include <errno.h>
+#include <stdio.h>
+#include <fcntl.h>
+#include <string.h>
+#include <byteswap.h>
+#include <sys/stat.h>
+
+
+static bool check_need_swap(int file_endian)
+{
+	const int data = 1;
+	u8 *check = (u8 *)&data;
+	int host_endian;
+
+	if (check[0] == 1)
+		host_endian = ELFDATA2LSB;
+	else
+		host_endian = ELFDATA2MSB;
+
+	return host_endian != file_endian;
+}
+
+#define NOTE_ALIGN(sz) (((sz) + 3) & ~3)
+
+#define NT_GNU_BUILD_ID	3
+
+static int read_build_id(void *note_data, size_t note_len, void *bf,
+			 size_t size, bool need_swap)
+{
+	struct {
+		u32 n_namesz;
+		u32 n_descsz;
+		u32 n_type;
+	} *nhdr;
+	void *ptr;
+
+	ptr = note_data;
+	while (ptr < (note_data + note_len)) {
+		const char *name;
+		size_t namesz, descsz;
+
+		nhdr = ptr;
+		if (need_swap) {
+			nhdr->n_namesz = bswap_32(nhdr->n_namesz);
+			nhdr->n_descsz = bswap_32(nhdr->n_descsz);
+			nhdr->n_type = bswap_32(nhdr->n_type);
+		}
+
+		namesz = NOTE_ALIGN(nhdr->n_namesz);
+		descsz = NOTE_ALIGN(nhdr->n_descsz);
+
+		ptr += sizeof(*nhdr);
+		name = ptr;
+		ptr += namesz;
+		if (nhdr->n_type == NT_GNU_BUILD_ID &&
+		    nhdr->n_namesz == sizeof("GNU")) {
+			if (memcmp(name, "GNU", sizeof("GNU")) == 0) {
+				size_t sz = min(size, descsz);
+				memcpy(bf, ptr, sz);
+				memset(bf + sz, 0, size - sz);
+				return 0;
+			}
+		}
+		ptr += descsz;
+	}
+
+	return -1;
+}
+
+int filename__read_debuglink(const char *filename __maybe_unused,
+			     char *debuglink __maybe_unused,
+			     size_t size __maybe_unused)
+{
+	return -1;
+}
+
+/*
+ * Just try PT_NOTE header otherwise fails
+ */
+int filename__read_build_id(const char *filename, void *bf, size_t size)
+{
+	FILE *fp;
+	int ret = -1;
+	bool need_swap = false;
+	u8 e_ident[EI_NIDENT];
+	size_t buf_size;
+	void *buf;
+	int i;
+
+	fp = fopen(filename, "r");
+	if (fp == NULL)
+		return -1;
+
+	if (fread(e_ident, sizeof(e_ident), 1, fp) != 1)
+		goto out;
+
+	if (memcmp(e_ident, ELFMAG, SELFMAG) ||
+	    e_ident[EI_VERSION] != EV_CURRENT)
+		goto out;
+
+	need_swap = check_need_swap(e_ident[EI_DATA]);
+
+	/* for simplicity */
+	fseek(fp, 0, SEEK_SET);
+
+	if (e_ident[EI_CLASS] == ELFCLASS32) {
+		Elf32_Ehdr ehdr;
+		Elf32_Phdr *phdr;
+
+		if (fread(&ehdr, sizeof(ehdr), 1, fp) != 1)
+			goto out;
+
+		if (need_swap) {
+			ehdr.e_phoff = bswap_32(ehdr.e_phoff);
+			ehdr.e_phentsize = bswap_16(ehdr.e_phentsize);
+			ehdr.e_phnum = bswap_16(ehdr.e_phnum);
+		}
+
+		buf_size = ehdr.e_phentsize * ehdr.e_phnum;
+		buf = malloc(buf_size);
+		if (buf == NULL)
+			goto out;
+
+		fseek(fp, ehdr.e_phoff, SEEK_SET);
+		if (fread(buf, buf_size, 1, fp) != 1)
+			goto out_free;
+
+		for (i = 0, phdr = buf; i < ehdr.e_phnum; i++, phdr++) {
+			void *tmp;
+			long offset;
+
+			if (need_swap) {
+				phdr->p_type = bswap_32(phdr->p_type);
+				phdr->p_offset = bswap_32(phdr->p_offset);
+				phdr->p_filesz = bswap_32(phdr->p_filesz);
+			}
+
+			if (phdr->p_type != PT_NOTE)
+				continue;
+
+			buf_size = phdr->p_filesz;
+			offset = phdr->p_offset;
+			tmp = realloc(buf, buf_size);
+			if (tmp == NULL)
+				goto out_free;
+
+			buf = tmp;
+			fseek(fp, offset, SEEK_SET);
+			if (fread(buf, buf_size, 1, fp) != 1)
+				goto out_free;
+
+			ret = read_build_id(buf, buf_size, bf, size, need_swap);
+			if (ret == 0)
+				ret = size;
+			break;
+		}
+	} else {
+		Elf64_Ehdr ehdr;
+		Elf64_Phdr *phdr;
+
+		if (fread(&ehdr, sizeof(ehdr), 1, fp) != 1)
+			goto out;
+
+		if (need_swap) {
+			ehdr.e_phoff = bswap_64(ehdr.e_phoff);
+			ehdr.e_phentsize = bswap_16(ehdr.e_phentsize);
+			ehdr.e_phnum = bswap_16(ehdr.e_phnum);
+		}
+
+		buf_size = ehdr.e_phentsize * ehdr.e_phnum;
+		buf = malloc(buf_size);
+		if (buf == NULL)
+			goto out;
+
+		fseek(fp, ehdr.e_phoff, SEEK_SET);
+		if (fread(buf, buf_size, 1, fp) != 1)
+			goto out_free;
+
+		for (i = 0, phdr = buf; i < ehdr.e_phnum; i++, phdr++) {
+			void *tmp;
+			long offset;
+
+			if (need_swap) {
+				phdr->p_type = bswap_32(phdr->p_type);
+				phdr->p_offset = bswap_64(phdr->p_offset);
+				phdr->p_filesz = bswap_64(phdr->p_filesz);
+			}
+
+			if (phdr->p_type != PT_NOTE)
+				continue;
+
+			buf_size = phdr->p_filesz;
+			offset = phdr->p_offset;
+			tmp = realloc(buf, buf_size);
+			if (tmp == NULL)
+				goto out_free;
+
+			buf = tmp;
+			fseek(fp, offset, SEEK_SET);
+			if (fread(buf, buf_size, 1, fp) != 1)
+				goto out_free;
+
+			ret = read_build_id(buf, buf_size, bf, size, need_swap);
+			if (ret == 0)
+				ret = size;
+			break;
+		}
+	}
+out_free:
+	free(buf);
+out:
+	fclose(fp);
+	return ret;
+}
+
+int sysfs__read_build_id(const char *filename, void *build_id, size_t size)
+{
+	int fd;
+	int ret = -1;
+	struct stat stbuf;
+	size_t buf_size;
+	void *buf;
+
+	fd = open(filename, O_RDONLY);
+	if (fd < 0)
+		return -1;
+
+	if (fstat(fd, &stbuf) < 0)
+		goto out;
+
+	buf_size = stbuf.st_size;
+	buf = malloc(buf_size);
+	if (buf == NULL)
+		goto out;
+
+	if (read(fd, buf, buf_size) != (ssize_t) buf_size)
+		goto out_free;
+
+	ret = read_build_id(buf, buf_size, build_id, size, false);
+out_free:
+	free(buf);
+out:
+	close(fd);
+	return ret;
+}
+
+int symsrc__init(struct symsrc *ss, struct dso *dso, const char *name,
+	         enum dso_binary_type type)
+{
+	int fd = open(name, O_RDONLY);
+	if (fd < 0)
+		goto out_errno;
+
+	ss->name = strdup(name);
+	if (!ss->name)
+		goto out_close;
+
+	ss->fd = fd;
+	ss->type = type;
+
+	return 0;
+out_close:
+	close(fd);
+out_errno:
+	dso->load_errno = errno;
+	return -1;
+}
+
+bool symsrc__possibly_runtime(struct symsrc *ss __maybe_unused)
+{
+	/* Assume all sym sources could be a runtime image. */
+	return true;
+}
+
+bool symsrc__has_symtab(struct symsrc *ss __maybe_unused)
+{
+	return false;
+}
+
+void symsrc__destroy(struct symsrc *ss)
+{
+	zfree(&ss->name);
+	close(ss->fd);
+}
+
+int dso__synthesize_plt_symbols(struct dso *dso __maybe_unused,
+				struct symsrc *ss __maybe_unused)
+{
+	return 0;
+}
+
+static int fd__is_64_bit(int fd)
+{
+	u8 e_ident[EI_NIDENT];
+
+	if (lseek(fd, 0, SEEK_SET))
+		return -1;
+
+	if (readn(fd, e_ident, sizeof(e_ident)) != sizeof(e_ident))
+		return -1;
+
+	if (memcmp(e_ident, ELFMAG, SELFMAG) ||
+	    e_ident[EI_VERSION] != EV_CURRENT)
+		return -1;
+
+	return e_ident[EI_CLASS] == ELFCLASS64;
+}
+
+enum dso_type dso__type_fd(int fd)
+{
+	Elf64_Ehdr ehdr;
+	int ret;
+
+	ret = fd__is_64_bit(fd);
+	if (ret < 0)
+		return DSO__TYPE_UNKNOWN;
+
+	if (ret)
+		return DSO__TYPE_64BIT;
+
+	if (readn(fd, &ehdr, sizeof(ehdr)) != sizeof(ehdr))
+		return DSO__TYPE_UNKNOWN;
+
+	if (ehdr.e_machine == EM_X86_64)
+		return DSO__TYPE_X32BIT;
+
+	return DSO__TYPE_32BIT;
+}
+
+int dso__load_sym(struct dso *dso, struct map *map __maybe_unused,
+		  struct symsrc *ss,
+		  struct symsrc *runtime_ss __maybe_unused,
+		  int kmodule __maybe_unused)
+{
+	unsigned char build_id[BUILD_ID_SIZE];
+	int ret;
+
+	ret = fd__is_64_bit(ss->fd);
+	if (ret >= 0)
+		dso->is_64_bit = ret;
+
+	if (filename__read_build_id(ss->name, build_id, BUILD_ID_SIZE) > 0) {
+		dso__set_build_id(dso, build_id);
+	}
+	return 0;
+}
+
+int file__read_maps(int fd __maybe_unused, bool exe __maybe_unused,
+		    mapfn_t mapfn __maybe_unused, void *data __maybe_unused,
+		    bool *is_64_bit __maybe_unused)
+{
+	return -1;
+}
+
+int kcore_extract__create(struct kcore_extract *kce __maybe_unused)
+{
+	return -1;
+}
+
+void kcore_extract__delete(struct kcore_extract *kce __maybe_unused)
+{
+}
+
+int kcore_copy(const char *from_dir __maybe_unused,
+	       const char *to_dir __maybe_unused)
+{
+	return -1;
+}
+
+void symbol__elf_init(void)
+{
+}
+
+char *dso__demangle_sym(struct dso *dso __maybe_unused,
+			int kmodule __maybe_unused,
+			const char *elf_name __maybe_unused)
+{
+	return NULL;
+}