Merge pull request #4526 from keszybz/coredump-python

Collect interpreter backtraces in systemd-coredump

4 files changed, 553 insertions, 3 deletions

diff --git a/src/basic/journal-importer.c b/src/basic/journal-importer.c
new file mode 100644
index 0000000000..4c13e46a49
--- /dev/null
+++ b/src/basic/journal-importer.c
@@ -0,0 +1,481 @@
+/***
+  This file is part of systemd.
+
+  Copyright 2014 Zbigniew Jędrzejewski-Szmek
+
+  systemd is free software; you can redistribute it and/or modify it
+  under the terms of the GNU Lesser General Public License as published by
+  the Free Software Foundation; either version 2.1 of the License, or
+  (at your option) any later version.
+
+  systemd is distributed in the hope that it will be useful, but
+  WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+  Lesser General Public License for more details.
+
+  You should have received a copy of the GNU Lesser General Public License
+  along with systemd; If not, see <http://www.gnu.org/licenses/>.
+***/
+
+#include <unistd.h>
+
+#include "alloc-util.h"
+#include "journal-importer.h"
+#include "fd-util.h"
+#include "parse-util.h"
+#include "string-util.h"
+
+enum {
+        IMPORTER_STATE_LINE = 0,    /* waiting to read, or reading line */
+        IMPORTER_STATE_DATA_START,  /* reading binary data header */
+        IMPORTER_STATE_DATA,        /* reading binary data */
+        IMPORTER_STATE_DATA_FINISH, /* expecting newline */
+        IMPORTER_STATE_EOF,         /* done */
+};
+
+static int iovw_put(struct iovec_wrapper *iovw, void* data, size_t len) {
+        if (!GREEDY_REALLOC(iovw->iovec, iovw->size_bytes, iovw->count + 1))
+                return log_oom();
+
+        iovw->iovec[iovw->count++] = (struct iovec) {data, len};
+        return 0;
+}
+
+static void iovw_free_contents(struct iovec_wrapper *iovw) {
+        iovw->iovec = mfree(iovw->iovec);
+        iovw->size_bytes = iovw->count = 0;
+}
+
+static void iovw_rebase(struct iovec_wrapper *iovw, char *old, char *new) {
+        size_t i;
+
+        for (i = 0; i < iovw->count; i++)
+                iovw->iovec[i].iov_base = (char*) iovw->iovec[i].iov_base - old + new;
+}
+
+size_t iovw_size(struct iovec_wrapper *iovw) {
+        size_t n = 0, i;
+
+        for (i = 0; i < iovw->count; i++)
+                n += iovw->iovec[i].iov_len;
+
+        return n;
+}
+
+void journal_importer_cleanup(JournalImporter *imp) {
+        if (imp->fd >= 0 && !imp->passive_fd) {
+                log_debug("Closing %s (fd=%d)", imp->name ?: "importer", imp->fd);
+                safe_close(imp->fd);
+        }
+
+        free(imp->buf);
+        iovw_free_contents(&imp->iovw);
+}
+
+static char* realloc_buffer(JournalImporter *imp, size_t size) {
+        char *b, *old = imp->buf;
+
+        b = GREEDY_REALLOC(imp->buf, imp->size, size);
+        if (!b)
+                return NULL;
+
+        iovw_rebase(&imp->iovw, old, imp->buf);
+
+        return b;
+}
+
+static int get_line(JournalImporter *imp, char **line, size_t *size) {
+        ssize_t n;
+        char *c = NULL;
+
+        assert(imp);
+        assert(imp->state == IMPORTER_STATE_LINE);
+        assert(imp->offset <= imp->filled);
+        assert(imp->filled <= imp->size);
+        assert(imp->buf == NULL || imp->size > 0);
+        assert(imp->fd >= 0);
+
+        for (;;) {
+                if (imp->buf) {
+                        size_t start = MAX(imp->scanned, imp->offset);
+
+                        c = memchr(imp->buf + start, '\n',
+                                   imp->filled - start);
+                        if (c != NULL)
+                                break;
+                }
+
+                imp->scanned = imp->filled;
+                if (imp->scanned >= DATA_SIZE_MAX) {
+                        log_error("Entry is bigger than %u bytes.", DATA_SIZE_MAX);
+                        return -E2BIG;
+                }
+
+                if (imp->passive_fd)
+                        /* we have to wait for some data to come to us */
+                        return -EAGAIN;
+
+                /* We know that imp->filled is at most DATA_SIZE_MAX, so if
+                   we reallocate it, we'll increase the size at least a bit. */
+                assert_cc(DATA_SIZE_MAX < ENTRY_SIZE_MAX);
+                if (imp->size - imp->filled < LINE_CHUNK &&
+                    !realloc_buffer(imp, MIN(imp->filled + LINE_CHUNK, ENTRY_SIZE_MAX)))
+                                return log_oom();
+
+                assert(imp->buf);
+                assert(imp->size - imp->filled >= LINE_CHUNK ||
+                       imp->size == ENTRY_SIZE_MAX);
+
+                n = read(imp->fd,
+                         imp->buf + imp->filled,
+                         imp->size - imp->filled);
+                if (n < 0) {
+                        if (errno != EAGAIN)
+                                log_error_errno(errno, "read(%d, ..., %zu): %m",
+                                                imp->fd,
+                                                imp->size - imp->filled);
+                        return -errno;
+                } else if (n == 0)
+                        return 0;
+
+                imp->filled += n;
+        }
+
+        *line = imp->buf + imp->offset;
+        *size = c + 1 - imp->buf - imp->offset;
+        imp->offset += *size;
+
+        return 1;
+}
+
+static int fill_fixed_size(JournalImporter *imp, void **data, size_t size) {
+
+        assert(imp);
+        assert(imp->state == IMPORTER_STATE_DATA_START ||
+               imp->state == IMPORTER_STATE_DATA ||
+               imp->state == IMPORTER_STATE_DATA_FINISH);
+        assert(size <= DATA_SIZE_MAX);
+        assert(imp->offset <= imp->filled);
+        assert(imp->filled <= imp->size);
+        assert(imp->buf != NULL || imp->size == 0);
+        assert(imp->buf == NULL || imp->size > 0);
+        assert(imp->fd >= 0);
+        assert(data);
+
+        while (imp->filled - imp->offset < size) {
+                int n;
+
+                if (imp->passive_fd)
+                        /* we have to wait for some data to come to us */
+                        return -EAGAIN;
+
+                if (!realloc_buffer(imp, imp->offset + size))
+                        return log_oom();
+
+                n = read(imp->fd, imp->buf + imp->filled,
+                         imp->size - imp->filled);
+                if (n < 0) {
+                        if (errno != EAGAIN)
+                                log_error_errno(errno, "read(%d, ..., %zu): %m", imp->fd,
+                                                imp->size - imp->filled);
+                        return -errno;
+                } else if (n == 0)
+                        return 0;
+
+                imp->filled += n;
+        }
+
+        *data = imp->buf + imp->offset;
+        imp->offset += size;
+
+        return 1;
+}
+
+static int get_data_size(JournalImporter *imp) {
+        int r;
+        void *data;
+
+        assert(imp);
+        assert(imp->state == IMPORTER_STATE_DATA_START);
+        assert(imp->data_size == 0);
+
+        r = fill_fixed_size(imp, &data, sizeof(uint64_t));
+        if (r <= 0)
+                return r;
+
+        imp->data_size = le64toh( *(uint64_t *) data );
+        if (imp->data_size > DATA_SIZE_MAX) {
+                log_error("Stream declares field with size %zu > DATA_SIZE_MAX = %u",
+                          imp->data_size, DATA_SIZE_MAX);
+                return -EINVAL;
+        }
+        if (imp->data_size == 0)
+                log_warning("Binary field with zero length");
+
+        return 1;
+}
+
+static int get_data_data(JournalImporter *imp, void **data) {
+        int r;
+
+        assert(imp);
+        assert(data);
+        assert(imp->state == IMPORTER_STATE_DATA);
+
+        r = fill_fixed_size(imp, data, imp->data_size);
+        if (r <= 0)
+                return r;
+
+        return 1;
+}
+
+static int get_data_newline(JournalImporter *imp) {
+        int r;
+        char *data;
+
+        assert(imp);
+        assert(imp->state == IMPORTER_STATE_DATA_FINISH);
+
+        r = fill_fixed_size(imp, (void**) &data, 1);
+        if (r <= 0)
+                return r;
+
+        assert(data);
+        if (*data != '\n') {
+                log_error("expected newline, got '%c'", *data);
+                return -EINVAL;
+        }
+
+        return 1;
+}
+
+static int process_dunder(JournalImporter *imp, char *line, size_t n) {
+        const char *timestamp;
+        int r;
+
+        assert(line);
+        assert(n > 0);
+        assert(line[n-1] == '\n');
+
+        /* XXX: is it worth to support timestamps in extended format?
+         * We don't produce them, but who knows... */
+
+        timestamp = startswith(line, "__CURSOR=");
+        if (timestamp)
+                /* ignore __CURSOR */
+                return 1;
+
+        timestamp = startswith(line, "__REALTIME_TIMESTAMP=");
+        if (timestamp) {
+                long long unsigned x;
+                line[n-1] = '\0';
+                r = safe_atollu(timestamp, &x);
+                if (r < 0)
+                        log_warning("Failed to parse __REALTIME_TIMESTAMP: '%s'", timestamp);
+                else
+                        imp->ts.realtime = x;
+                return r < 0 ? r : 1;
+        }
+
+        timestamp = startswith(line, "__MONOTONIC_TIMESTAMP=");
+        if (timestamp) {
+                long long unsigned x;
+                line[n-1] = '\0';
+                r = safe_atollu(timestamp, &x);
+                if (r < 0)
+                        log_warning("Failed to parse __MONOTONIC_TIMESTAMP: '%s'", timestamp);
+                else
+                        imp->ts.monotonic = x;
+                return r < 0 ? r : 1;
+        }
+
+        timestamp = startswith(line, "__");
+        if (timestamp) {
+                log_notice("Unknown dunder line %s", line);
+                return 1;
+        }
+
+        /* no dunder */
+        return 0;
+}
+
+int journal_importer_process_data(JournalImporter *imp) {
+        int r;
+
+        switch(imp->state) {
+        case IMPORTER_STATE_LINE: {
+                char *line, *sep;
+                size_t n = 0;
+
+                assert(imp->data_size == 0);
+
+                r = get_line(imp, &line, &n);
+                if (r < 0)
+                        return r;
+                if (r == 0) {
+                        imp->state = IMPORTER_STATE_EOF;
+                        return r;
+                }
+                assert(n > 0);
+                assert(line[n-1] == '\n');
+
+                if (n == 1) {
+                        log_trace("Received empty line, event is ready");
+                        return 1;
+                }
+
+                r = process_dunder(imp, line, n);
+                if (r != 0)
+                        return r < 0 ? r : 0;
+
+                /* MESSAGE=xxx\n
+                   or
+                   COREDUMP\n
+                   LLLLLLLL0011223344...\n
+                */
+                sep = memchr(line, '=', n);
+                if (sep) {
+                        /* chomp newline */
+                        n--;
+
+                        r = iovw_put(&imp->iovw, line, n);
+                        if (r < 0)
+                                return r;
+                } else {
+                        /* replace \n with = */
+                        line[n-1] = '=';
+
+                        imp->field_len = n;
+                        imp->state = IMPORTER_STATE_DATA_START;
+
+                        /* we cannot put the field in iovec until we have all data */
+                }
+
+                log_trace("Received: %.*s (%s)", (int) n, line, sep ? "text" : "binary");
+
+                return 0; /* continue */
+        }
+
+        case IMPORTER_STATE_DATA_START:
+                assert(imp->data_size == 0);
+
+                r = get_data_size(imp);
+                // log_debug("get_data_size() -> %d", r);
+                if (r < 0)
+                        return r;
+                if (r == 0) {
+                        imp->state = IMPORTER_STATE_EOF;
+                        return 0;
+                }
+
+                imp->state = imp->data_size > 0 ?
+                        IMPORTER_STATE_DATA : IMPORTER_STATE_DATA_FINISH;
+
+                return 0; /* continue */
+
+        case IMPORTER_STATE_DATA: {
+                void *data;
+                char *field;
+
+                assert(imp->data_size > 0);
+
+                r = get_data_data(imp, &data);
+                // log_debug("get_data_data() -> %d", r);
+                if (r < 0)
+                        return r;
+                if (r == 0) {
+                        imp->state = IMPORTER_STATE_EOF;
+                        return 0;
+                }
+
+                assert(data);
+
+                field = (char*) data - sizeof(uint64_t) - imp->field_len;
+                memmove(field + sizeof(uint64_t), field, imp->field_len);
+
+                r = iovw_put(&imp->iovw, field + sizeof(uint64_t), imp->field_len + imp->data_size);
+                if (r < 0)
+                        return r;
+
+                imp->state = IMPORTER_STATE_DATA_FINISH;
+
+                return 0; /* continue */
+        }
+
+        case IMPORTER_STATE_DATA_FINISH:
+                r = get_data_newline(imp);
+                // log_debug("get_data_newline() -> %d", r);
+                if (r < 0)
+                        return r;
+                if (r == 0) {
+                        imp->state = IMPORTER_STATE_EOF;
+                        return 0;
+                }
+
+                imp->data_size = 0;
+                imp->state = IMPORTER_STATE_LINE;
+
+                return 0; /* continue */
+        default:
+                assert_not_reached("wtf?");
+        }
+}
+
+int journal_importer_push_data(JournalImporter *imp, const char *data, size_t size) {
+        assert(imp);
+        assert(imp->state != IMPORTER_STATE_EOF);
+
+        if (!realloc_buffer(imp, imp->filled + size)) {
+                log_error("Failed to store received data of size %zu "
+                          "(in addition to existing %zu bytes with %zu filled): %s",
+                          size, imp->size, imp->filled, strerror(ENOMEM));
+                return -ENOMEM;
+        }
+
+        memcpy(imp->buf + imp->filled, data, size);
+        imp->filled += size;
+
+        return 0;
+}
+
+void journal_importer_drop_iovw(JournalImporter *imp) {
+        size_t remain, target;
+
+        /* This function drops processed data that along with the iovw that points at it */
+
+        iovw_free_contents(&imp->iovw);
+
+        /* possibly reset buffer position */
+        remain = imp->filled - imp->offset;
+
+        if (remain == 0) /* no brainer */
+                imp->offset = imp->scanned = imp->filled = 0;
+        else if (imp->offset > imp->size - imp->filled &&
+                 imp->offset > remain) {
+                memcpy(imp->buf, imp->buf + imp->offset, remain);
+                imp->offset = imp->scanned = 0;
+                imp->filled = remain;
+        }
+
+        target = imp->size;
+        while (target > 16 * LINE_CHUNK && imp->filled < target / 2)
+                target /= 2;
+        if (target < imp->size) {
+                char *tmp;
+
+                tmp = realloc(imp->buf, target);
+                if (!tmp)
+                        log_warning("Failed to reallocate buffer to (smaller) size %zu",
+                                    target);
+                else {
+                        log_debug("Reallocated buffer from %zu to %zu bytes",
+                                  imp->size, target);
+                        imp->buf = tmp;
+                        imp->size = target;
+                }
+        }
+}
+
+bool journal_importer_eof(const JournalImporter *imp) {
+        return imp->state == IMPORTER_STATE_EOF;
+}
diff --git a/src/basic/journal-importer.h b/src/basic/journal-importer.h
new file mode 100644
index 0000000000..b3e308dd6d
--- /dev/null
+++ b/src/basic/journal-importer.h
@@ -0,0 +1,70 @@
+/***
+  This file is part of systemd.
+
+  Copyright 2016 Zbigniew Jędrzejewski-Szmek
+
+  systemd is free software; you can redistribute it and/or modify it
+  under the terms of the GNU Lesser General Public License as published by
+  the Free Software Foundation; either version 2.1 of the License, or
+  (at your option) any later version.
+
+  systemd is distributed in the hope that it will be useful, but
+  WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+  Lesser General Public License for more details.
+
+  You should have received a copy of the GNU Lesser General Public License
+  along with systemd; If not, see <http://www.gnu.org/licenses/>.
+***/
+
+#pragma once
+
+#include <stddef.h>
+#include <stdbool.h>
+#include <sys/uio.h>
+
+#include "time-util.h"
+
+/* Make sure not to make this smaller than the maximum coredump size.
+ * See COREDUMP_MAX in coredump.c */
+#define ENTRY_SIZE_MAX (1024*1024*770u)
+#define DATA_SIZE_MAX (1024*1024*768u)
+#define LINE_CHUNK 8*1024u
+
+struct iovec_wrapper {
+        struct iovec *iovec;
+        size_t size_bytes;
+        size_t count;
+};
+
+size_t iovw_size(struct iovec_wrapper *iovw);
+
+typedef struct JournalImporter {
+        int fd;
+        bool passive_fd;
+        char *name;
+
+        char *buf;
+        size_t size;       /* total size of the buffer */
+        size_t offset;     /* offset to the beginning of live data in the buffer */
+        size_t scanned;    /* number of bytes since the beginning of data without a newline */
+        size_t filled;     /* total number of bytes in the buffer */
+
+        size_t field_len;  /* used for binary fields: the field name length */
+        size_t data_size;  /* and the size of the binary data chunk being processed */
+
+        struct iovec_wrapper iovw;
+
+        int state;
+        dual_timestamp ts;
+} JournalImporter;
+
+void journal_importer_cleanup(JournalImporter *);
+int journal_importer_process_data(JournalImporter *);
+int journal_importer_push_data(JournalImporter *, const char *data, size_t size);
+void journal_importer_drop_iovw(JournalImporter *);
+bool journal_importer_eof(const JournalImporter *);
+
+static inline size_t journal_importer_bytes_remaining(const JournalImporter *imp) {
+        return imp->filled;
+}
diff --git a/src/basic/log.c b/src/basic/log.c
index 1362b1c086..e6d2d61d72 100644
--- a/src/basic/log.c
+++ b/src/basic/log.c
@@ -1164,7 +1164,7 @@ int log_syntax_internal(
         return log_struct_internal(
                         level, error,
                         file, line, func,
-                        LOG_MESSAGE_ID(SD_MESSAGE_INVALID_CONFIGURATION),
+                        "MESSAGE_ID=" SD_MESSAGE_INVALID_CONFIGURATION_STR,
                         "CONFIG_FILE=%s", config_file,
                         "CONFIG_LINE=%u", config_line,
                         LOG_MESSAGE("%s:%u: %s", config_file, config_line, buffer),
diff --git a/src/basic/log.h b/src/basic/log.h
index 2afee20bb5..9cacbb6b70 100644
--- a/src/basic/log.h
+++ b/src/basic/log.h
@@ -214,9 +214,8 @@ bool log_on_console(void) _pure_;
 const char *log_target_to_string(LogTarget target) _const_;
 LogTarget log_target_from_string(const char *s) _pure_;
 
-/* Helpers to prepare various fields for structured logging */
+/* Helper to prepare various field for structured logging */
 #define LOG_MESSAGE(fmt, ...) "MESSAGE=" fmt, ##__VA_ARGS__
-#define LOG_MESSAGE_ID(x) "MESSAGE_ID=" SD_ID128_FORMAT_STR, SD_ID128_FORMAT_VAL(x)
 
 void log_received_signal(int level, const struct signalfd_siginfo *si);