+/*
+ * Copyright (C) 2011 David Goulet <david.goulet@polymtl.ca>
+ * Copyright (C) 2014 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
+ *
+ * SPDX-License-Identifier: GPL-2.0-only
+ *
+ */
+
+#include <getopt.h>
+#include <signal.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <sys/mman.h>
+#include <fcntl.h>
+#include <sys/wait.h>
+#include <unistd.h>
+#include <ctype.h>
+#include <dirent.h>
+#include <common/compat/endian.h>
+#include <inttypes.h>
+#include <stdbool.h>
+
+#include <version.h>
+#include <lttng/lttng.h>
+#include <common/common.h>
+#include <common/spawn-viewer.h>
+#include <common/utils.h>
+
+#define COPY_BUFLEN 4096
+#define RB_CRASH_DUMP_ABI_LEN 32
+
+#define RB_CRASH_DUMP_ABI_MAGIC_LEN 16
+
+/*
+ * The 128-bit magic number is xor'd in the process data so it does not
+ * cause a false positive when searching for buffers by scanning memory.
+ * The actual magic number is:
+ * 0x17, 0x7B, 0xF1, 0x77, 0xBF, 0x17, 0x7B, 0xF1,
+ * 0x77, 0xBF, 0x17, 0x7B, 0xF1, 0x77, 0xBF, 0x17,
+ */
+#define RB_CRASH_DUMP_ABI_MAGIC_XOR \
+ { \
+ 0x17 ^ 0xFF, 0x7B ^ 0xFF, 0xF1 ^ 0xFF, 0x77 ^ 0xFF, \
+ 0xBF ^ 0xFF, 0x17 ^ 0xFF, 0x7B ^ 0xFF, 0xF1 ^ 0xFF, \
+ 0x77 ^ 0xFF, 0xBF ^ 0xFF, 0x17 ^ 0xFF, 0x7B ^ 0xFF, \
+ 0xF1 ^ 0xFF, 0x77 ^ 0xFF, 0xBF ^ 0xFF, 0x17 ^ 0xFF, \
+ }
+
+static const char *help_msg =
+#ifdef LTTNG_EMBED_HELP
+#include <lttng-crash.1.h>
+#else
+NULL
+#endif
+;
+
+/*
+ * Non-static to ensure the compiler does not optimize away the xor.
+ */
+uint8_t lttng_crash_expected_magic_xor[] = RB_CRASH_DUMP_ABI_MAGIC_XOR;
+
+#define RB_CRASH_ENDIAN 0x1234
+#define RB_CRASH_ENDIAN_REVERSE 0x3412
+
+enum lttng_crash_type {
+ LTTNG_CRASH_TYPE_UST = 0,
+ LTTNG_CRASH_TYPE_KERNEL = 1,
+};
+
+/* LTTng ring buffer defines (copied) */
+
+#define HALF_ULONG_BITS(wl) (((wl) * CHAR_BIT) >> 1)
+
+#define SB_ID_OFFSET_SHIFT(wl) (HALF_ULONG_BITS(wl) + 1)
+#define SB_ID_OFFSET_COUNT(wl) (1UL << SB_ID_OFFSET_SHIFT(wl))
+#define SB_ID_OFFSET_MASK(wl) (~(SB_ID_OFFSET_COUNT(wl) - 1))
+/*
+ * Lowest bit of top word half belongs to noref. Used only for overwrite mode.
+ */
+#define SB_ID_NOREF_SHIFT(wl) (SB_ID_OFFSET_SHIFT(wl) - 1)
+#define SB_ID_NOREF_COUNT(wl) (1UL << SB_ID_NOREF_SHIFT(wl))
+#define SB_ID_NOREF_MASK(wl) SB_ID_NOREF_COUNT(wl)
+/*
+ * In overwrite mode: lowest half of word is used for index.
+ * Limit of 2^16 subbuffers per buffer on 32-bit, 2^32 on 64-bit.
+ * In producer-consumer mode: whole word used for index.
+ */
+#define SB_ID_INDEX_SHIFT(wl) 0
+#define SB_ID_INDEX_COUNT(wl) (1UL << SB_ID_INDEX_SHIFT(wl))
+#define SB_ID_INDEX_MASK(wl) (SB_ID_NOREF_COUNT(wl) - 1)
+
+enum rb_modes {
+ RING_BUFFER_OVERWRITE = 0, /* Overwrite when buffer full */
+ RING_BUFFER_DISCARD = 1, /* Discard when buffer full */
+};
+
+struct crash_abi_unknown {
+ uint8_t magic[RB_CRASH_DUMP_ABI_MAGIC_LEN];
+ uint64_t mmap_length; /* Overall length of crash record */
+ uint16_t endian; /*
+ * { 0x12, 0x34 }: big endian
+ * { 0x34, 0x12 }: little endian
+ */
+ uint16_t major; /* Major number. */
+ uint16_t minor; /* Minor number. */
+ uint8_t word_size; /* Word size (bytes). */
+ uint8_t layout_type; /* enum lttng_crash_layout */
+} __attribute__((packed));
+
+struct crash_abi_0_0 {
+ struct crash_abi_unknown parent;
+
+ struct {
+ uint32_t prod_offset;
+ uint32_t consumed_offset;
+ uint32_t commit_hot_array;
+ uint32_t commit_hot_seq;
+ uint32_t buf_wsb_array;
+ uint32_t buf_wsb_id;
+ uint32_t sb_array;
+ uint32_t sb_array_shmp_offset;
+ uint32_t sb_backend_p_offset;
+ uint32_t content_size;
+ uint32_t packet_size;
+ } __attribute__((packed)) offset;
+ struct {
+ uint8_t prod_offset;
+ uint8_t consumed_offset;
+ uint8_t commit_hot_seq;
+ uint8_t buf_wsb_id;
+ uint8_t sb_array_shmp_offset;
+ uint8_t sb_backend_p_offset;
+ uint8_t content_size;
+ uint8_t packet_size;
+ } __attribute__((packed)) length;
+ struct {
+ uint32_t commit_hot_array;
+ uint32_t buf_wsb_array;
+ uint32_t sb_array;
+ } __attribute__((packed)) stride;
+
+ uint64_t buf_size; /* Size of the buffer */
+ uint64_t subbuf_size; /* Sub-buffer size */
+ uint64_t num_subbuf; /* Number of sub-buffers for writer */
+ uint32_t mode; /* Buffer mode: 0: overwrite, 1: discard */
+} __attribute__((packed));
+
+struct lttng_crash_layout {
+ struct {
+ int prod_offset, consumed_offset,
+ commit_hot_array, commit_hot_seq,
+ buf_wsb_array, buf_wsb_id,
+ sb_array, sb_array_shmp_offset,
+ sb_backend_p_offset, content_size,
+ packet_size;
+ } offset;
+ struct {
+ int prod_offset, consumed_offset,
+ commit_hot_seq, buf_wsb_id,
+ sb_array_shmp_offset, sb_backend_p_offset,
+ content_size, packet_size;
+ } length;
+ struct {
+ int commit_hot_array, buf_wsb_array, sb_array;
+ } stride;
+
+ int reverse_byte_order;
+ int word_size;
+
+ uint64_t mmap_length; /* Length of crash record */
+ uint64_t buf_size; /* Size of the buffer */
+ uint64_t subbuf_size; /* Sub-buffer size */
+ uint64_t num_subbuf; /* Number of sub-buffers for writer */
+ uint32_t mode; /* Buffer mode: 0: overwrite, 1: discard */
+};
+
+/* Variables */
+static const char *progname;
+static char *opt_viewer_path = NULL;
+static char *opt_output_path = NULL;
+
+static char *the_input_path;
+
+int lttng_opt_quiet, lttng_opt_verbose, lttng_opt_mi;
+
+enum {
+ OPT_DUMP_OPTIONS,
+};
+
+/* Getopt options. No first level command. */
+static struct option long_options[] = {
+ { "version", 0, NULL, 'V' },
+ { "help", 0, NULL, 'h' },
+ { "verbose", 0, NULL, 'v' },
+ { "viewer", 1, NULL, 'e' },
+ { "extract", 1, NULL, 'x' },
+ { "list-options", 0, NULL, OPT_DUMP_OPTIONS },
+ { NULL, 0, NULL, 0 },
+};
+
+static void usage(void)
+{
+ int ret = utils_show_help(1, "lttng-crash", help_msg);
+
+ if (ret) {
+ ERR("Cannot show --help for `lttng-crash`");
+ perror("exec");
+ exit(EXIT_FAILURE);
+ }
+}
+
+static void version(FILE *ofp)
+{
+ fprintf(ofp, "%s (LTTng Crash Trace Viewer) " VERSION " - " VERSION_NAME
+ "%s%s\n",
+ progname,
+ GIT_VERSION[0] == '\0' ? "" : " - " GIT_VERSION,
+ EXTRA_VERSION_NAME[0] == '\0' ? "" : " - " EXTRA_VERSION_NAME);
+}
+
+/*
+ * list_options
+ *
+ * List options line by line. This is mostly for bash auto completion and to
+ * avoid difficult parsing.
+ */
+static void list_options(FILE *ofp)
+{
+ int i = 0;
+ struct option *option = NULL;
+
+ option = &long_options[i];
+ while (option->name != NULL) {
+ fprintf(ofp, "--%s\n", option->name);
+
+ if (isprint(option->val)) {
+ fprintf(ofp, "-%c\n", option->val);
+ }
+
+ i++;
+ option = &long_options[i];
+ }
+}
+
+/*
+ * Parse command line arguments.
+ *
+ * Return 0 if OK, else -1
+ */
+static int parse_args(int argc, char **argv)
+{
+ int opt, ret = 0;
+
+ if (argc < 2) {
+ usage();
+ exit(EXIT_FAILURE);
+ }
+
+ while ((opt = getopt_long(argc, argv, "+Vhve:x:", long_options, NULL)) != -1) {
+ switch (opt) {
+ case 'V':
+ version(stdout);
+ ret = 1;
+ goto end;
+ case 'h':
+ usage();
+ ret = 1;
+ goto end;
+ case 'v':
+ /* There is only 3 possible level of verbosity. (-vvv) */
+ if (lttng_opt_verbose < 3) {
+ lttng_opt_verbose += 1;
+ }
+ break;
+ case 'e':
+ free(opt_viewer_path);
+ opt_viewer_path = strdup(optarg);
+ break;
+ case 'x':
+ free(opt_output_path);
+ opt_output_path = strdup(optarg);
+ break;
+ case OPT_DUMP_OPTIONS:
+ list_options(stdout);
+ ret = 1;
+ goto end;
+ default:
+ ERR("Unknown command-line option");
+ goto error;
+ }
+ }
+
+ /* No leftovers, or more than one input path, print usage and quit */
+ if (argc - optind != 1) {
+ ERR("Command-line error: Specify exactly one input path");
+ goto error;
+ }
+
+ the_input_path = argv[optind];
+end:
+ return ret;
+
+error:
+ return -1;
+}
+
+static
+int copy_file(const char *file_dest, const char *file_src)
+{
+ int fd_src = -1, fd_dest = -1;
+ ssize_t readlen, writelen;
+ char buf[COPY_BUFLEN];
+ int ret;
+
+ DBG("Copy metadata file '%s' into '%s'", file_src, file_dest);
+
+ fd_src = open(file_src, O_RDONLY);
+ if (fd_src < 0) {
+ PERROR("Error opening %s for reading", file_src);
+ ret = -errno;
+ goto error;
+ }
+ fd_dest = open(file_dest, O_RDWR | O_CREAT | O_EXCL,
+ S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP);
+ if (fd_dest < 0) {
+ PERROR("Error opening %s for writing", file_dest);
+ ret = -errno;
+ goto error;
+ }
+
+ for (;;) {
+ readlen = lttng_read(fd_src, buf, COPY_BUFLEN);
+ if (readlen < 0) {
+ PERROR("Error reading input file");
+ ret = -1;
+ goto error;
+ }
+ if (!readlen) {
+ break;
+ }
+ writelen = lttng_write(fd_dest, buf, readlen);
+ if (writelen < readlen) {
+ PERROR("Error writing to output file");
+ ret = -1;
+ goto error;
+ }
+ }
+
+ ret = 0;
+error:
+ if (fd_src >= 0) {
+ if (close(fd_src) < 0) {
+ PERROR("Error closing %s", file_src);
+ }
+ }
+
+ if (fd_dest >= 0) {
+ if (close(fd_dest) < 0) {
+ PERROR("Error closing %s", file_dest);
+ }
+ }
+ return ret;
+}
+
+static
+uint64_t _crash_get_field(const struct lttng_crash_layout *layout,
+ const char *ptr, size_t size)
+{
+ switch (size) {
+ case 1: return *(uint8_t *) ptr;
+ case 2: if (layout->reverse_byte_order) {
+ return bswap_16(*(uint16_t *) ptr);
+ } else {
+ return *(uint16_t *) ptr;
+
+ }
+ case 4: if (layout->reverse_byte_order) {
+ return bswap_32(*(uint32_t *) ptr);
+ } else {
+ return *(uint32_t *) ptr;
+
+ }
+ case 8: if (layout->reverse_byte_order) {
+ return bswap_64(*(uint64_t *) ptr);
+ } else {
+ return *(uint64_t *) ptr;
+ }
+ default:
+ abort();
+ return -1;
+ }
+
+}
+
+#define crash_get_field(layout, map, name) \
+ _crash_get_field(layout, (map) + (layout)->offset.name, \
+ layout->length.name)
+
+#define crash_get_array_field(layout, map, array_name, idx, field_name) \
+ _crash_get_field(layout, \
+ (map) + (layout)->offset.array_name \
+ + (idx * (layout)->stride.array_name) \
+ + (layout)->offset.field_name, \
+ (layout)->length.field_name)
+
+#define crash_get_hdr_raw_field(layout, hdr, name) ((hdr)->name)
+
+#define crash_get_hdr_field(layout, hdr, name) \
+ _crash_get_field(layout, (const char *) &(hdr)->name, \
+ sizeof((hdr)->name))
+
+#define crash_get_layout(layout, hdr, name) \
+ do { \
+ (layout)->name = crash_get_hdr_field(layout, hdr, \
+ name); \
+ DBG("layout.%s = %" PRIu64, #name, \
+ (uint64_t) (layout)->name); \
+ } while (0)
+
+static
+int get_crash_layout_0_0(struct lttng_crash_layout *layout,
+ char *map)
+{
+ const struct crash_abi_0_0 *abi = (const struct crash_abi_0_0 *) map;
+
+ crash_get_layout(layout, abi, offset.prod_offset);
+ crash_get_layout(layout, abi, offset.consumed_offset);
+ crash_get_layout(layout, abi, offset.commit_hot_array);
+ crash_get_layout(layout, abi, offset.commit_hot_seq);
+ crash_get_layout(layout, abi, offset.buf_wsb_array);
+ crash_get_layout(layout, abi, offset.buf_wsb_id);
+ crash_get_layout(layout, abi, offset.sb_array);
+ crash_get_layout(layout, abi, offset.sb_array_shmp_offset);
+ crash_get_layout(layout, abi, offset.sb_backend_p_offset);
+ crash_get_layout(layout, abi, offset.content_size);
+ crash_get_layout(layout, abi, offset.packet_size);
+
+ crash_get_layout(layout, abi, length.prod_offset);
+ crash_get_layout(layout, abi, length.consumed_offset);
+ crash_get_layout(layout, abi, length.commit_hot_seq);
+ crash_get_layout(layout, abi, length.buf_wsb_id);
+ crash_get_layout(layout, abi, length.sb_array_shmp_offset);
+ crash_get_layout(layout, abi, length.sb_backend_p_offset);
+ crash_get_layout(layout, abi, length.content_size);
+ crash_get_layout(layout, abi, length.packet_size);
+
+ crash_get_layout(layout, abi, stride.commit_hot_array);
+ crash_get_layout(layout, abi, stride.buf_wsb_array);
+ crash_get_layout(layout, abi, stride.sb_array);
+
+ crash_get_layout(layout, abi, buf_size);
+ crash_get_layout(layout, abi, subbuf_size);
+ crash_get_layout(layout, abi, num_subbuf);
+ crash_get_layout(layout, abi, mode);
+
+ return 0;
+}
+
+static
+void print_dbg_magic(const uint8_t *magic)
+{
+ DBG("magic: 0x%X%X%X%X%X%X%X%X%X%X%X%X%X%X%X%X",
+ magic[0], magic[1], magic[2], magic[3],
+ magic[4], magic[5], magic[6], magic[7],
+ magic[8], magic[9], magic[10], magic[11],
+ magic[12], magic[13], magic[14], magic[15]);
+}
+
+static
+int check_magic(const uint8_t *magic)
+{
+ int i;
+
+ for (i = 0; i < RB_CRASH_DUMP_ABI_MAGIC_LEN; i++) {
+ if ((magic[i] ^ 0xFF) != lttng_crash_expected_magic_xor[i]) {
+ return -1;
+ }
+ }
+ return 0;
+}
+
+static
+int get_crash_layout(struct lttng_crash_layout *layout, int fd,
+ const char *input_file)
+{
+ char *map;
+ int ret = 0, unmapret;
+ const uint8_t *magic;
+ uint64_t mmap_length;
+ uint16_t major, minor;
+ uint8_t word_size;
+ const struct crash_abi_unknown *abi;
+ uint16_t endian;
+ enum lttng_crash_type layout_type;
+ struct stat stat;
+
+ ret = fstat(fd, &stat);
+ if (ret < 0) {
+ PERROR("Failed to fstat '%s'", input_file);
+ return -1;
+ }
+ if (stat.st_size < RB_CRASH_DUMP_ABI_LEN) {
+ ERR("File '%s' truncated: file length of %" PRIi64
+ " bytes does not meet the minimal expected "
+ "length of %d bytes",
+ input_file, (int64_t) stat.st_size,
+ RB_CRASH_DUMP_ABI_LEN);
+ return -1;
+ }
+ map = (char *) mmap(NULL, RB_CRASH_DUMP_ABI_LEN, PROT_READ, MAP_PRIVATE,
+ fd, 0);
+ if (map == MAP_FAILED) {
+ PERROR("Mapping file");
+ return -1;
+ }
+ abi = (const struct crash_abi_unknown *) map;
+ magic = crash_get_hdr_raw_field(layout, abi, magic);
+ print_dbg_magic(magic);
+ if (check_magic(magic)) {
+ DBG("Unknown magic number");
+ ret = 1; /* positive return value, skip */
+ goto end;
+ }
+ endian = crash_get_hdr_field(layout, abi, endian);
+ switch (endian) {
+ case RB_CRASH_ENDIAN:
+ break;
+ case RB_CRASH_ENDIAN_REVERSE:
+ layout->reverse_byte_order = 1;
+ break;
+ default:
+ DBG("Unknown endianness value: 0x%X", (unsigned int) endian);
+ ret = 1; /* positive return value, skip */
+ goto end;
+ }
+ layout_type = (enum lttng_crash_type) crash_get_hdr_field(layout, abi, layout_type);
+ switch (layout_type) {
+ case LTTNG_CRASH_TYPE_UST:
+ break;
+ case LTTNG_CRASH_TYPE_KERNEL:
+ ERR("lttng-modules buffer layout support not implemented");
+ ret = 1; /* positive return value, skip */
+ goto end;
+ default:
+ ERR("Unknown layout type %u", (unsigned int) layout_type);
+ ret = 1; /* positive return value, skip */
+ goto end;
+ }
+ mmap_length = crash_get_hdr_field(layout, abi, mmap_length);
+ DBG("mmap_length: %" PRIu64, mmap_length);
+ layout->mmap_length = mmap_length;
+ major = crash_get_hdr_field(layout, abi, major);
+ DBG("major: %u", major);
+ minor = crash_get_hdr_field(layout, abi, minor);
+ DBG("minor: %u", minor);
+ word_size = crash_get_hdr_field(layout, abi, word_size);
+ DBG("word_size: %u", word_size);
+ switch (major) {
+ case 0:
+ switch (minor) {
+ case 0:
+ ret = get_crash_layout_0_0(layout, map);
+ if (ret)
+ goto end;
+ break;
+ default:
+ ret = -1;
+ ERR("Unsupported crash ABI %u.%u\n", major, minor);
+ goto end;
+ }
+ break;
+ default:
+ ERR("Unsupported crash ABI %u.%u\n", major, minor);
+ ret = -1;
+ goto end;
+ }
+ layout->word_size = word_size;
+end:
+ unmapret = munmap(map, RB_CRASH_DUMP_ABI_LEN);
+ if (unmapret) {
+ PERROR("munmap");
+ }
+ return ret;
+}
+
+/* buf_trunc mask selects only the buffer number. */
+static inline
+uint64_t buf_trunc(uint64_t offset, uint64_t buf_size)
+{
+ return offset & ~(buf_size - 1);
+}
+
+/* subbuf_trunc mask selects the subbuffer number. */
+static inline
+uint64_t subbuf_trunc(uint64_t offset, uint64_t subbuf_size)
+{
+ return offset & ~(subbuf_size - 1);
+}
+
+/* buf_offset mask selects only the offset within the current buffer. */
+static inline
+uint64_t buf_offset(uint64_t offset, uint64_t buf_size)
+{
+ return offset & (buf_size - 1);
+}
+
+/* subbuf_offset mask selects the offset within the current subbuffer. */
+static inline
+uint64_t subbuf_offset(uint64_t offset, uint64_t subbuf_size)
+{
+ return offset & (subbuf_size - 1);
+}
+
+/* subbuf_index returns the index of the current subbuffer within the buffer. */
+static inline
+uint64_t subbuf_index(uint64_t offset, uint64_t buf_size, uint64_t subbuf_size)
+{
+ return buf_offset(offset, buf_size) / subbuf_size;
+}
+
+static inline
+uint64_t subbuffer_id_get_index(uint32_t mode, uint64_t id,
+ unsigned int wl)
+{
+ if (mode == RING_BUFFER_OVERWRITE)
+ return id & SB_ID_INDEX_MASK(wl);
+ else
+ return id;
+}
+
+static
+int copy_crash_subbuf(const struct lttng_crash_layout *layout,
+ int fd_dest, char *buf, uint64_t offset)
+{
+ uint64_t buf_size, subbuf_size, num_subbuf, sbidx, id,
+ sb_bindex, rpages_offset, p_offset, seq_cc,
+ committed, commit_count_mask, consumed_cur,
+ packet_size;
+ char *subbuf_ptr;
+ ssize_t writelen;
+
+ /*
+ * Get the current subbuffer by applying the proper mask to
+ * "offset", and looking up the subbuf location within the
+ * source file buf.
+ */
+
+ buf_size = layout->buf_size;
+ subbuf_size = layout->subbuf_size;
+ num_subbuf = layout->num_subbuf;
+
+ switch (layout->word_size) {
+ case 4: commit_count_mask = 0xFFFFFFFFULL / num_subbuf;
+ break;
+ case 8: commit_count_mask = 0xFFFFFFFFFFFFFFFFULL / num_subbuf;
+ break;
+ default:
+ ERR("Unsupported word size: %u",
+ (unsigned int) layout->word_size);
+ return -EINVAL;
+ }
+
+ DBG("Copy crash subbuffer at offset %" PRIu64, offset);
+ sbidx = subbuf_index(offset, buf_size, subbuf_size);
+
+ /*
+ * Find where the seq cc is located. Compute length of data to
+ * copy.
+ */
+ seq_cc = crash_get_array_field(layout, buf, commit_hot_array,
+ sbidx, commit_hot_seq);
+ consumed_cur = crash_get_field(layout, buf, consumed_offset);
+
+ /*
+ * Check that the buffer we are getting is after or at
+ * consumed_cur position.
+ */
+ if ((long) subbuf_trunc(offset, subbuf_size)
+ - (long) subbuf_trunc(consumed_cur, subbuf_size) < 0) {
+ DBG("No data: position is before consumed_cur");
+ goto nodata;
+ }
+
+ /*
+ * Check if subbuffer has been fully committed.
+ */
+ if (((seq_cc - subbuf_size) & commit_count_mask)
+ - (buf_trunc(offset, buf_size) / num_subbuf)
+ == 0) {
+ committed = subbuf_size;
+ } else {
+ committed = subbuf_offset(seq_cc, subbuf_size);
+ if (!committed) {
+ DBG("No data committed, seq_cc: %" PRIu64, seq_cc);
+ goto nodata;
+ }
+ }
+
+ /* Find actual physical offset in subbuffer table */
+ id = crash_get_array_field(layout, buf, buf_wsb_array,
+ sbidx, buf_wsb_id);
+ sb_bindex = subbuffer_id_get_index(layout->mode, id,
+ layout->word_size);
+ rpages_offset = crash_get_array_field(layout, buf, sb_array,
+ sb_bindex, sb_array_shmp_offset);
+ p_offset = crash_get_field(layout, buf + rpages_offset,
+ sb_backend_p_offset);
+ subbuf_ptr = buf + p_offset;
+
+ if (committed == subbuf_size) {
+ /*
+ * Packet header can be used.
+ */
+ if (layout->length.packet_size) {
+ memcpy(&packet_size,
+ subbuf_ptr + layout->offset.packet_size,
+ layout->length.packet_size);
+ if (layout->reverse_byte_order) {
+ packet_size = bswap_64(packet_size);
+ }
+ packet_size /= CHAR_BIT;
+ } else {
+ packet_size = subbuf_size;
+ }
+ } else {
+ uint64_t patch_size;
+
+ /*
+ * Find where to patch the sub-buffer header with actual
+ * readable data len and packet len, derived from seq
+ * cc. Patch it in our in-memory copy.
+ */
+ patch_size = committed * CHAR_BIT;
+ if (layout->reverse_byte_order) {
+ patch_size = bswap_64(patch_size);
+ }
+ if (layout->length.content_size) {
+ memcpy(subbuf_ptr + layout->offset.content_size,
+ &patch_size, layout->length.content_size);
+ }
+ if (layout->length.packet_size) {
+ memcpy(subbuf_ptr + layout->offset.packet_size,
+ &patch_size, layout->length.packet_size);
+ }
+ packet_size = committed;
+ }
+
+ /*
+ * Copy packet into fd_dest.
+ */
+ writelen = lttng_write(fd_dest, subbuf_ptr, packet_size);
+ if (writelen < packet_size) {
+ PERROR("Error writing to output file");
+ return -1;
+ }
+ DBG("Copied %" PRIu64 " bytes of data", packet_size);
+ return 0;
+
+nodata:
+ return -ENODATA;
+}
+
+static
+int copy_crash_data(const struct lttng_crash_layout *layout, int fd_dest,
+ int fd_src)
+{
+ char *buf;
+ int ret = 0, has_data = 0;
+ struct stat statbuf;
+ size_t src_file_len;
+ uint64_t prod_offset, consumed_offset;
+ uint64_t offset, subbuf_size;
+ ssize_t readlen;
+
+ ret = fstat(fd_src, &statbuf);
+ if (ret) {
+ return ret;
+ }
+ src_file_len = layout->mmap_length;
+ buf = (char *) zmalloc(src_file_len);
+ if (!buf) {
+ return -1;
+ }
+ readlen = lttng_read(fd_src, buf, src_file_len);
+ if (readlen < 0) {
+ PERROR("Error reading input file");
+ ret = -1;
+ goto end;
+ }
+
+ prod_offset = crash_get_field(layout, buf, prod_offset);
+ DBG("prod_offset: 0x%" PRIx64, prod_offset);
+ consumed_offset = crash_get_field(layout, buf, consumed_offset);
+ DBG("consumed_offset: 0x%" PRIx64, consumed_offset);
+ subbuf_size = layout->subbuf_size;
+
+ for (offset = consumed_offset; offset < prod_offset;
+ offset += subbuf_size) {
+ ret = copy_crash_subbuf(layout, fd_dest, buf, offset);
+ if (!ret) {
+ has_data = 1;
+ }
+ if (ret) {
+ goto end;
+ }
+ }
+end:
+ free(buf);
+ if (ret && ret != -ENODATA) {
+ return ret;
+ }
+ if (has_data) {
+ return 0;
+ } else {
+ return -ENODATA;
+ }
+}
+
+static
+int extract_file(int output_dir_fd, const char *output_file,
+ int input_dir_fd, const char *input_file)
+{
+ int fd_dest, fd_src, ret = 0, closeret;
+ struct lttng_crash_layout layout;
+
+ layout.reverse_byte_order = 0; /* For reading magic number */
+
+ DBG("Extract file '%s'", input_file);
+ fd_src = openat(input_dir_fd, input_file, O_RDONLY);
+ if (fd_src < 0) {
+ PERROR("Error opening '%s' for reading",
+ input_file);
+ ret = -1;
+ goto end;
+ }
+
+ /* Query the crash ABI layout */
+ ret = get_crash_layout(&layout, fd_src, input_file);
+ if (ret) {
+ goto close_src;
+ }
+
+ fd_dest = openat(output_dir_fd, output_file,
+ O_RDWR | O_CREAT | O_EXCL,
+ S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP);
+ if (fd_dest < 0) {
+ PERROR("Error opening '%s' for writing",
+ output_file);
+ ret = -1;
+ goto close_src;
+ }
+
+ ret = copy_crash_data(&layout, fd_dest, fd_src);
+ if (ret) {
+ goto close_dest;
+ }
+
+close_dest:
+ closeret = close(fd_dest);
+ if (closeret) {
+ PERROR("close");
+ }
+ if (ret == -ENODATA) {
+ closeret = unlinkat(output_dir_fd, output_file, 0);
+ if (closeret) {
+ PERROR("unlinkat");
+ }
+ }
+close_src:
+ closeret = close(fd_src);
+ if (closeret) {
+ PERROR("close");
+ }
+end:
+ return ret;
+}
+
+static
+int extract_all_files(const char *output_path,
+ const char *input_path)
+{
+ DIR *input_dir, *output_dir;
+ int input_dir_fd, output_dir_fd, ret = 0, closeret;
+ struct dirent *entry; /* input */
+
+ /* Open input directory */
+ input_dir = opendir(input_path);
+ if (!input_dir) {
+ PERROR("Cannot open '%s' path", input_path);
+ return -1;
+ }
+ input_dir_fd = dirfd(input_dir);
+ if (input_dir_fd < 0) {
+ PERROR("dirfd");
+ return -1;
+ }
+
+ /* Open output directory */
+ output_dir = opendir(output_path);
+ if (!output_dir) {
+ PERROR("Cannot open '%s' path", output_path);
+ return -1;
+ }
+ output_dir_fd = dirfd(output_dir);
+ if (output_dir_fd < 0) {
+ PERROR("dirfd");
+ return -1;
+ }
+
+ while ((entry = readdir(input_dir))) {
+ if (!strcmp(entry->d_name, ".")
+ || !strcmp(entry->d_name, ".."))
+ continue;
+ ret = extract_file(output_dir_fd, entry->d_name,
+ input_dir_fd, entry->d_name);
+ if (ret == -ENODATA) {
+ DBG("No data in file '%s', skipping", entry->d_name);
+ ret = 0;
+ continue;
+ } else if (ret < 0) {
+ break;
+ } else if (ret > 0) {
+ DBG("Skipping file '%s'", entry->d_name);
+ ret = 0;
+ continue;
+ }
+ }
+ closeret = closedir(output_dir);
+ if (closeret) {
+ PERROR("closedir");
+ }
+ closeret = closedir(input_dir);
+ if (closeret) {
+ PERROR("closedir");
+ }
+ return ret;
+}
+
+static
+int extract_one_trace(const char *output_path,
+ const char *input_path)
+{
+ char dest[PATH_MAX], src[PATH_MAX];
+ int ret;
+
+ DBG("Extract crash trace '%s' into '%s'", input_path, output_path);
+
+ /* Copy metadata */
+ strncpy(dest, output_path, PATH_MAX);
+ dest[PATH_MAX - 1] = '\0';
+ strncat(dest, "/metadata", PATH_MAX - strlen(dest) - 1);
+
+ strncpy(src, input_path, PATH_MAX);
+ src[PATH_MAX - 1] = '\0';
+ strncat(src, "/metadata", PATH_MAX - strlen(dest) - 1);
+
+ ret = copy_file(dest, src);
+ if (ret) {
+ return ret;
+ }
+
+ /* Extract each other file that has expected header */
+ return extract_all_files(output_path, input_path);
+}
+
+static
+int extract_trace_recursive(const char *output_path,
+ const char *input_path)
+{
+ DIR *dir;
+ int dir_fd, ret = 0, closeret;
+ struct dirent *entry;
+ size_t path_len;
+ int has_warning = 0;
+
+ /* Open directory */
+ dir = opendir(input_path);
+ if (!dir) {
+ PERROR("Cannot open '%s' path", input_path);
+ return -1;
+ }
+
+ path_len = strlen(input_path);
+
+ dir_fd = dirfd(dir);
+ if (dir_fd < 0) {
+ PERROR("dirfd");
+ return -1;
+ }
+
+ while ((entry = readdir(dir))) {
+ struct stat st;
+ size_t name_len;
+ char filename[PATH_MAX];
+
+ if (!strcmp(entry->d_name, ".")
+ || !strcmp(entry->d_name, "..")) {
+ continue;
+ }
+
+ name_len = strlen(entry->d_name);
+ if (path_len + name_len + 2 > sizeof(filename)) {
+ ERR("Failed to remove file: path name too long (%s/%s)",
+ input_path, entry->d_name);
+ continue;
+ }
+
+ if (snprintf(filename, sizeof(filename), "%s/%s",
+ input_path, entry->d_name) < 0) {
+ ERR("Failed to format path.");
+ continue;
+ }
+
+ if (stat(filename, &st)) {
+ PERROR("stat");
+ continue;
+ }
+
+ if (S_ISDIR(st.st_mode)) {
+ char output_subpath[PATH_MAX];
+ char input_subpath[PATH_MAX];
+
+ strncpy(output_subpath, output_path,
+ sizeof(output_subpath));
+ output_subpath[sizeof(output_subpath) - 1] = '\0';
+ strncat(output_subpath, "/",
+ sizeof(output_subpath) - strlen(output_subpath) - 1);
+ strncat(output_subpath, entry->d_name,
+ sizeof(output_subpath) - strlen(output_subpath) - 1);
+
+ ret = mkdir(output_subpath, S_IRWXU | S_IRWXG);
+ if (ret) {
+ PERROR("mkdir");
+ has_warning = 1;
+ goto end;
+ }
+
+ strncpy(input_subpath, input_path,
+ sizeof(input_subpath));
+ input_subpath[sizeof(input_subpath) - 1] = '\0';
+ strncat(input_subpath, "/",
+ sizeof(input_subpath) - strlen(input_subpath) - 1);
+ strncat(input_subpath, entry->d_name,
+ sizeof(input_subpath) - strlen(input_subpath) - 1);
+
+ ret = extract_trace_recursive(output_subpath,
+ input_subpath);
+ if (ret) {
+ has_warning = 1;
+ }
+ } else if (S_ISREG(st.st_mode) || S_ISLNK(st.st_mode)) {
+ if (!strcmp(entry->d_name, "metadata")) {
+ ret = extract_one_trace(output_path,
+ input_path);
+ if (ret) {
+ WARN("Error extracting trace '%s', continuing anyway.",
+ input_path);
+ has_warning = 1;
+ }
+ }
+ } else {
+ has_warning = 1;
+ goto end;
+ }
+ }
+end:
+ closeret = closedir(dir);
+ if (closeret) {
+ PERROR("closedir");
+ }
+ return has_warning;
+}
+
+static
+int delete_dir_recursive(const char *path)
+{
+ DIR *dir;
+ int dir_fd, ret = 0, closeret;
+ size_t path_len;
+ struct dirent *entry;
+
+ /* Open trace directory */
+ dir = opendir(path);
+ if (!dir) {
+ PERROR("Cannot open '%s' path", path);
+ ret = -errno;
+ goto end_no_closedir;
+ }
+
+ path_len = strlen(path);
+
+ dir_fd = dirfd(dir);
+ if (dir_fd < 0) {
+ PERROR("dirfd");
+ ret = -errno;
+ goto end;
+ }
+
+ while ((entry = readdir(dir))) {
+ struct stat st;
+ size_t name_len;
+ char filename[PATH_MAX];
+
+ if (!strcmp(entry->d_name, ".")
+ || !strcmp(entry->d_name, "..")) {
+ continue;
+ }
+
+ name_len = strlen(entry->d_name);
+ if (path_len + name_len + 2 > sizeof(filename)) {
+ ERR("Failed to remove file: path name too long (%s/%s)",
+ path, entry->d_name);
+ continue;
+ }
+
+ if (snprintf(filename, sizeof(filename), "%s/%s",
+ path, entry->d_name) < 0) {
+ ERR("Failed to format path.");
+ continue;
+ }
+
+ if (stat(filename, &st)) {
+ PERROR("stat");
+ continue;
+ }
+
+ if (S_ISDIR(st.st_mode)) {
+ char *subpath = (char *) zmalloc(PATH_MAX);
+
+ if (!subpath) {
+ PERROR("zmalloc path");
+ ret = -1;
+ goto end;
+ }
+ strncpy(subpath, path, PATH_MAX);
+ subpath[PATH_MAX - 1] = '\0';
+ strncat(subpath, "/",
+ PATH_MAX - strlen(subpath) - 1);
+ strncat(subpath, entry->d_name,
+ PATH_MAX - strlen(subpath) - 1);
+
+ ret = delete_dir_recursive(subpath);
+ free(subpath);
+ if (ret) {
+ /* Error occurred, abort traversal. */
+ goto end;
+ }
+ } else if (S_ISREG(st.st_mode)) {
+ ret = unlinkat(dir_fd, entry->d_name, 0);
+ if (ret) {
+ PERROR("Unlinking '%s'", entry->d_name);
+ goto end;
+ }
+ } else {
+ ret = -EINVAL;
+ goto end;
+ }
+ }
+end:
+ if (!ret) {
+ ret = rmdir(path);
+ if (ret) {
+ PERROR("rmdir '%s'", path);
+ }
+ }
+ closeret = closedir(dir);
+ if (closeret) {
+ PERROR("closedir");
+ }
+end_no_closedir:
+ return ret;
+}
+
+static
+int view_trace(const char *trace_path, char *viewer_path)
+{
+ pid_t pid;
+
+ pid = fork();
+ if (pid < 0) {
+ /* Error */
+ PERROR("fork");
+ return -1;
+ } else if (pid > 0) {
+ /* Parent */
+ int status;
+
+ pid = waitpid(pid, &status, 0);
+ if (pid < 0 || !WIFEXITED(status)) {
+ return -1;
+ }
+ } else {
+ /* Child */
+ int ret;
+
+ ret = spawn_viewer(trace_path, viewer_path, false);
+ if (ret) {
+ exit(EXIT_FAILURE);
+ }
+ /* Never reached */
+ exit(EXIT_SUCCESS);
+ }
+ return 0;
+}
+
+/*
+ * main
+ */
+int main(int argc, char *argv[])
+{
+ int ret;
+ bool has_warning = false;
+ const char *output_path = NULL;
+ char tmppath[] = "/tmp/lttng-crash-XXXXXX";
+
+ progname = argv[0] ? argv[0] : "lttng-crash";
+
+ ret = parse_args(argc, argv);
+ if (ret > 0) {
+ goto end;
+ } else if (ret < 0) {
+ has_warning = true;
+ goto end;
+ }
+
+ if (opt_output_path) {
+ output_path = opt_output_path;
+ ret = mkdir(output_path, S_IRWXU | S_IRWXG);
+ if (ret) {
+ PERROR("mkdir");
+ has_warning = true;
+ goto end;
+ }
+ } else {
+ output_path = mkdtemp(tmppath);
+ if (!output_path) {
+ PERROR("mkdtemp");
+ has_warning = true;
+ goto end;
+ }
+ }
+
+ ret = extract_trace_recursive(output_path, the_input_path);
+ if (ret < 0) {
+ has_warning = true;
+ goto end;
+ } else if (ret > 0) {
+ /* extract_trace_recursive reported a warning. */
+ has_warning = true;
+ }
+ if (!opt_output_path) {
+ /* View trace */
+ ret = view_trace(output_path, opt_viewer_path);
+ if (ret) {
+ has_warning = true;
+ }
+ /* unlink temporary trace */
+ ret = delete_dir_recursive(output_path);
+ if (ret) {
+ has_warning = true;
+ }
+ }
+end:
+ exit(has_warning ? EXIT_FAILURE : EXIT_SUCCESS);
+}