crash-stack: deprecate corefile option

crash-stack should be able to generate call stack
using pid only.
(Generating corefile causes sluggish issue)

Change-Id: Ie9e74494b966838d1dd6548424d51bfd2df4c1e0

1 files changed, 10 insertions, 249 deletions

diff --git a/src/crash-stack/crash-stack.c b/src/crash-stack/crash-stack.c
index 63a2b4a..ea4dbc5 100644
--- a/src/crash-stack/crash-stack.c
+++ b/src/crash-stack/crash-stack.c
@@ -48,12 +48,6 @@
 
 #include <elfutils/version.h>
 #include <elfutils/libdwfl.h>
-/*
- * In case the program is compiled with core dumps, the license may switch to GPL2.
- */
-#ifdef WITH_CORE_DUMP
-#include <elfutils/libebl.h>
-#endif
 
 #define BUF_SIZE (BUFSIZ)
 #define HEXA 16
@@ -426,53 +420,6 @@ static Dwfl *__open_dwfl_with_pid(pid_t pid, pid_t tid)
 }
 
 /**
- * @brief Opens libdwfl for using with core dump file
- *
- * @remarks This function will open core file regardless of WITH_CORE_DUMP setting.
- *          It may help with detecting issues with using dwfl even without support
- *          for dumps.
- *
- * @param core elf handler for the core dump file
- * @param core_file_name name of the core file; needed only for diagnostics
- * @return Dwfl handle
- */
-static Dwfl *__open_dwfl_with_core(Elf *core, const char *core_file_name)
-{
-	static const Dwfl_Callbacks core_callbacks = {
-		.find_elf = dwfl_build_id_find_elf,
-		.find_debuginfo = dwfl_standard_find_debuginfo,
-		.section_address = NULL,
-		.debuginfo_path = NULL
-	};
-
-	Dwfl *dwfl = dwfl_begin(&core_callbacks);
-	if (dwfl == NULL) {
-		fprintf(errfile, "%s : Can't start dwfl (%s)\n", core_file_name, dwfl_errmsg(-1));
-		return NULL;
-	}
-
-#if _ELFUTILS_PREREQ(0,158)
-	if (dwfl_core_file_report(dwfl, core, NULL) < 0)
-#else
-		if (dwfl_core_file_report(dwfl, core) < 0)
-#endif
-		{
-			fprintf(errfile, "%s : dwfl report failed (%s)\n", core_file_name, dwfl_errmsg(-1));
-			dwfl_end(dwfl);
-			return NULL;
-		}
-
-#if _ELFUTILS_PREREQ(0,158)
-	if (dwfl_core_file_attach(dwfl, core) < 0) {
-		fprintf(errfile, "%s : dwfl attach failed (%s)\n", core_file_name, dwfl_errmsg(-1));
-		dwfl_end(dwfl);
-		return NULL;
-	}
-#endif
-	return dwfl;
-}
-
-/**
  * @brief Gets registers information for live process
  *
  * @param pid pid of the live process
@@ -540,163 +487,6 @@ static int __get_signal_ptrace(pid_t pid)
 	return 0;
 }
 
-#ifdef WITH_CORE_DUMP
-/**
- * @brief Helper function for updating mappings.
- *
- * @remarks Old versions of libelf not always extract full information about modules.
- *          For such cases we maintain mappings for every module. Those mappings
- *          may be updated while reading notes from core file.
- *
- * @param mappings mappings database
- * @param mapping_start address of the mapped start of the module; module is identified
- *                      by mapping_start
- * @param mapping_end address of the end of the module; needed to compute module boundaries
- * @param offset offset within core file - unused
- * @param name file name of the module
- */
-static void __updateMapping(Mappings *mappings, uint64_t mapping_start, uint64_t mapping_end,
-		uint64_t offset, const char *name)
-{
-	int i;
-	for (i = 0; i < mappings->elems; i++) {
-		if (mappings->tab[i].m_start == mapping_start) {
-			mappings->tab[i].m_end = mapping_end;
-			mappings->tab[i].m_name = name;
-			mappings->tab[i].m_offset = offset;
-			mappings->tab[i].m_fd = open(name, O_RDONLY);
-			mappings->tab[i].m_elf = elf_begin(mappings->tab[i].m_fd, ELF_C_READ_MMAP, NULL);
-			return;
-		}
-	}
-}
-#endif
-
-/**
- * @brief Gets registers from core dump
- *
- * @param core ELF handler for the core dump file
- * @param core_file_name name of the core file; needed only for diagnostics
- * @param mappings mappings database
- * @return notes handler, NULL on error
- */
-static Elf_Data *__get_registers_core(Elf *core, const char *core_file_name, Mappings *mappings)
-{
-	Elf_Data *notes = NULL;
-	/* The part below uses libebl. In case WITH_CORE_DUMP is enabled, the license
-	 * may switch to GPL2.
-	 */
-#ifdef WITH_CORE_DUMP
-	GElf_Phdr mem;
-	GElf_Phdr *phdr = gelf_getphdr(core, 0, &mem);
-
-	if (phdr == NULL || phdr->p_type != PT_NOTE) {
-		fprintf(errfile, "%s : Missing note section at the first position in core file\n",
-				core_file_name);
-		return NULL;
-	}
-
-	notes = elf_getdata_rawchunk(core, phdr->p_offset, phdr->p_filesz, ELF_T_NHDR);
-	if (notes == NULL) {
-		fprintf(errfile, "%s : error getting notes (%s)\n", core_file_name, dwfl_errmsg(-1));
-		return NULL;
-	}
-
-	Ebl *ebl = ebl_openbackend(core);
-	if (ebl == NULL) {
-		fprintf(errfile, "%s : Can't initialize ebl\n", core_file_name);
-		return NULL;
-	}
-
-	GElf_Nhdr nhdr;
-	size_t name_pos;
-	size_t desc_pos;
-	size_t pos = 0;
-	size_t new_pos = 0;
-	int got_regs = 0;
-	/* registers should be in the first note! */
-	while ((new_pos = gelf_getnote(notes, pos, &nhdr, &name_pos, &desc_pos)) > 0) {
-		if (nhdr.n_type == NT_PRSTATUS && !got_regs) {
-			GElf_Word regs_offset;
-			size_t nregloc;
-			const Ebl_Register_Location *reglocs;
-			size_t nitems;
-			const Ebl_Core_Item *items;
-
-			got_regs = 1;
-
-			if (0 == ebl_core_note(ebl, &nhdr, "CORE", &regs_offset, &nregloc,
-						&reglocs, &nitems, &items)) {
-				fprintf(errfile,
-						"%s : error parsing notes (built with different build of libebl?)\n",
-						core_file_name);
-				return NULL;
-			}
-
-			const char *regs_location = (const char *)(notes->d_buf) + pos + desc_pos
-				+ regs_offset;
-			unsigned i;
-
-			for (i = 0; i < nregloc; i++) {
-				const char *register_location = regs_location + reglocs[i].offset;
-				int regnum;
-				for (regnum = reglocs[i].regno;
-						regnum < reglocs[i].regno + reglocs[i].count;
-						regnum++) {
-					char regname[5];
-					int bits, type;
-					const char *prefix = 0;
-					const char *setname = 0;
-
-					ssize_t ret = ebl_register_info(ebl, regnum, regname,
-							sizeof(regname), &prefix, &setname,
-							&bits, &type);
-					if (ret < 0) {
-						fprintf(errfile, "%s : can't get register info\n", core_file_name);
-						return NULL;
-					}
-					void *place_for_reg_value = _get_place_for_register_value(regname, regnum);
-
-					if (place_for_reg_value != NULL)
-						__get_value(core, register_location, bits, place_for_reg_value);
-
-					register_location += bits / 8 + reglocs[i].pad;
-				}
-			}
-		} else if (nhdr.n_type == NT_FILE) {
-			uint64_t values_cnt = 0, page_size = 0;
-			const char *values;
-			const char *filenames;
-			size_t addr_size = 0;
-
-			__parse_note_file(core, notes->d_buf + desc_pos, &values_cnt, &page_size,
-					&addr_size, &values, &filenames);
-
-			int ii;
-			/* First: triplets of <mapping-start> <mapping-end> <offset-in-pages>
-			 *     count = values_cnt
-			 * Then the names of files.
-			 */
-			for (ii = 0; ii < values_cnt; ii++) {
-				uint64_t mapping_start = 0, mapping_end = 0, offset_in_pages = 0;
-				const char *item = values + 3 * addr_size * ii;
-
-				__get_mapping_item(core, addr_size, item, &mapping_start, &mapping_end,
-						&offset_in_pages);
-				__updateMapping(mappings, mapping_start, mapping_end,
-						offset_in_pages*page_size, filenames);
-				filenames += strlen(filenames)+1;
-			}
-		}
-		pos = new_pos;
-	}
-	ebl_closebackend(ebl);
-#else
-	fprintf(errfile, "Configured without support for core dump files\n");
-#endif
-	return notes;
-}
-
 /**
  * @brief Resolves procedure and module names using libdwfl
  *
@@ -1203,8 +993,6 @@ int main(int argc, char **argv)
 	pid_t pid = 0;
 	pid_t tid = 0;
 
-	const char *core_file_name;
-
 	prctl(PR_SET_DUMPABLE, 0);
 
 	while ((c = getopt_long_only(argc, argv, "", opts, NULL)) != -1) {
@@ -1229,39 +1017,20 @@ int main(int argc, char **argv)
 
 	if (tid == 0) tid = pid;
 
-	core_file_name = argv[optind];
 	argc -= optind;
 
 	elf_version(EV_CURRENT);
 
 	/* First, prepare dwfl and modules */
-	Elf *core = NULL;
-	int core_fd = -1;
 	Dwfl *dwfl = NULL;
 
 	if (pid > 1)
 		dwfl = __open_dwfl_with_pid(pid, tid);
 	else {
-		if (argc != 1) {
-			fprintf(errfile,
-					"Usage: %s [--output file] [--erroutput file] [--pid <pid> [--tid <tid>] | <core-file>]\n",
-					argv[0]);
-			return 1;
-		}
-
-		core_fd = open(core_file_name, O_RDONLY);
-		if (core_fd < 0) {
-			perror(core_file_name);
-			return 2;
-		}
-
-		core = elf_begin(core_fd, ELF_C_READ_MMAP, NULL);
-		if (core == NULL) {
-			fprintf(errfile, "%s : Can't open ELF (%s)\n", core_file_name, elf_errmsg(-1));
-			return 3;
-		}
-
-		dwfl = __open_dwfl_with_core(core, core_file_name);
+		fprintf(errfile,
+				"Usage: %s [--output file] [--erroutput file] [--pid <pid> [--tid <tid>]]\n",
+				argv[0]);
+		return 1;
 	}
 
 	if (NULL == dwfl)
@@ -1277,25 +1046,19 @@ int main(int argc, char **argv)
 	__crash_stack_print_exe(outputfile, pid);
 
 	/* Now, get registers */
-	if (pid > 1) {
-		if (-1 == __get_signal_ptrace(pid))
-			return 4444;
-		if (-1 == __get_registers_ptrace(tid))
-			return 3333;
-	} else {
-		notes = __get_registers_core(core, core_file_name, &mappings);
-		if (NULL == notes)
-			return 2222;
-	}
+	if (-1 == __get_signal_ptrace(pid))
+		return 4444;
+	if (-1 == __get_registers_ptrace(tid))
+		return 3333;
 
 	/* Unwind call stack */
 	Callstack callstack;
 	callstack_constructor(&callstack);
 
-	_create_crash_stack(dwfl, core, tid, &mappings, &callstack);
+	_create_crash_stack(dwfl, NULL, tid, &mappings, &callstack);
 	size_t it;
 	for (it = 0; it != callstack.elems; ++it)
-		__resolve_symbols(&callstack.proc[it], dwfl, core, notes);
+		__resolve_symbols(&callstack.proc[it], dwfl, NULL, notes);
 
 	/* Print registers */
 	_crash_stack_print_regs(outputfile);
@@ -1316,8 +1079,6 @@ int main(int argc, char **argv)
 	callstack_destructor(&callstack);
 	dwfl_report_end(dwfl, NULL, NULL);
 	dwfl_end(dwfl);
-	if (NULL != core) elf_end(core);
-	if (-1 != core_fd) close(core_fd);
 
 	return 0;
 }