bootctl: add listing of loader entries

3 files changed, 395 insertions, 0 deletions

diff --git a/src/shared/bootspec.c b/src/shared/bootspec.c
new file mode 100644
index 0000000000..8394f4fe35
--- /dev/null
+++ b/src/shared/bootspec.c
@@ -0,0 +1,335 @@
+/***
+  This file is part of systemd.
+
+  Copyright 2017 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 <stdio.h>
+
+#include "alloc-util.h"
+#include "bootspec.h"
+#include "conf-files.h"
+#include "def.h"
+#include "efivars.h"
+#include "fd-util.h"
+#include "fileio.h"
+#include "string-util.h"
+#include "strv.h"
+
+void boot_entry_free(BootEntry *entry) {
+        free(entry->filename);
+
+        free(entry->title);
+        free(entry->version);
+        free(entry->machine_id);
+        free(entry->architecture);
+        strv_free(entry->options);
+        free(entry->kernel);
+        free(entry->efi);
+        strv_free(entry->initrd);
+        free(entry->device_tree);
+}
+
+int boot_entry_load(const char *path, BootEntry *entry) {
+        _cleanup_fclose_ FILE *f = NULL;
+        unsigned line = 1;
+        _cleanup_(boot_entry_free) BootEntry tmp = {};
+        int r;
+
+        f = fopen(path, "re");
+        if (!f)
+                return log_error_errno(errno, "Failed to open \"%s\": %m", path);
+
+        tmp.filename = strdup(basename(path));
+        if (!tmp.filename)
+                return log_oom();
+
+        for (;;) {
+                _cleanup_free_ char *buf = NULL;
+                char *p;
+
+                r = read_line(f, LONG_LINE_MAX, &buf);
+                if (r == 0)
+                        break;
+                if (r == -ENOBUFS)
+                        return log_error_errno(r, "%s:%u: Line too long", path, line);
+                if (r < 0)
+                        return log_error_errno(r, "%s:%u: Error while reading: %m", path, line);
+
+                line++;
+
+                if (IN_SET(*strstrip(buf), '#', '\0'))
+                        continue;
+
+                p = strchr(buf, ' ');
+                if (!p) {
+                        log_warning("%s:%u: Bad syntax", path, line);
+                        continue;
+                }
+                *p = '\0';
+                p = strstrip(p + 1);
+
+                if (streq(buf, "title"))
+                        r = free_and_strdup(&tmp.title, p);
+                else if (streq(buf, "version"))
+                        r = free_and_strdup(&tmp.version, p);
+                else if (streq(buf, "machine-id"))
+                        r = free_and_strdup(&tmp.machine_id, p);
+                else if (streq(buf, "architecture"))
+                        r = free_and_strdup(&tmp.architecture, p);
+                else if (streq(buf, "options"))
+                        r = strv_extend(&tmp.options, p);
+                else if (streq(buf, "linux"))
+                        r = free_and_strdup(&tmp.kernel, p);
+                else if (streq(buf, "efi"))
+                        r = free_and_strdup(&tmp.efi, p);
+                else if (streq(buf, "initrd"))
+                        r = strv_extend(&tmp.initrd, p);
+                else if (streq(buf, "devicetree"))
+                        r = free_and_strdup(&tmp.device_tree, p);
+                else {
+                        log_notice("%s:%u: Unknown line \"%s\"", path, line, buf);
+                        continue;
+                }
+                if (r < 0)
+                        return log_error_errno(r, "%s:%u: Error while reading: %m", path, line);
+        }
+
+        *entry = tmp;
+        tmp = (BootEntry) {};
+        return 0;
+}
+
+void boot_config_free(BootConfig *config) {
+        unsigned i;
+
+        free(config->default_pattern);
+        free(config->timeout);
+        free(config->editor);
+
+        free(config->entry_oneshot);
+        free(config->entry_default);
+
+        for (i = 0; i < config->n_entries; i++)
+                boot_entry_free(config->entries + i);
+        free(config->entries);
+}
+
+int boot_loader_read_conf(const char *path, BootConfig *config) {
+        _cleanup_fclose_ FILE *f = NULL;
+        unsigned line = 1;
+        int r;
+
+        f = fopen(path, "re");
+        if (!f)
+                return log_error_errno(errno, "Failed to open \"%s\": %m", path);
+
+        for (;;) {
+                _cleanup_free_ char *buf = NULL;
+                char *p;
+
+                r = read_line(f, LONG_LINE_MAX, &buf);
+                if (r == 0)
+                        break;
+                if (r == -ENOBUFS)
+                        return log_error_errno(r, "%s:%u: Line too long", path, line);
+                if (r < 0)
+                        return log_error_errno(r, "%s:%u: Error while reading: %m", path, line);
+
+                line++;
+
+                if (IN_SET(*strstrip(buf), '#', '\0'))
+                        continue;
+
+                p = strchr(buf, ' ');
+                if (!p) {
+                        log_warning("%s:%u: Bad syntax", path, line);
+                        continue;
+                }
+                *p = '\0';
+                p = strstrip(p + 1);
+
+                if (streq(buf, "default"))
+                        r = free_and_strdup(&config->default_pattern, p);
+                else if (streq(buf, "timeout"))
+                        r = free_and_strdup(&config->timeout, p);
+                else if (streq(buf, "editor"))
+                        r = free_and_strdup(&config->editor, p);
+                else {
+                        log_notice("%s:%u: Unknown line \"%s\"", path, line, buf);
+                        continue;
+                }
+                if (r < 0)
+                        return log_error_errno(r, "%s:%u: Error while reading: %m", path, line);
+        }
+
+        return 0;
+}
+
+/* This is a direct translation of str_verscmp from boot.c */
+static bool is_digit(int c) {
+        return c >= '0' && c <= '9';
+}
+
+static int c_order(int c) {
+        if (c == '\0')
+                return 0;
+        if (is_digit(c))
+                return 0;
+        else if ((c >= 'a') && (c <= 'z'))
+                return c;
+        else
+                return c + 0x10000;
+}
+
+static int str_verscmp(const char *s1, const char *s2) {
+        const char *os1 = s1;
+        const char *os2 = s2;
+
+        while (*s1 || *s2) {
+                int first;
+
+                while ((*s1 && !is_digit(*s1)) || (*s2 && !is_digit(*s2))) {
+                        int order;
+
+                        order = c_order(*s1) - c_order(*s2);
+                        if (order)
+                                return order;
+                        s1++;
+                        s2++;
+                }
+
+                while (*s1 == '0')
+                        s1++;
+                while (*s2 == '0')
+                        s2++;
+
+                first = 0;
+                while (is_digit(*s1) && is_digit(*s2)) {
+                        if (first == 0)
+                                first = *s1 - *s2;
+                        s1++;
+                        s2++;
+                }
+
+                if (is_digit(*s1))
+                        return 1;
+                if (is_digit(*s2))
+                        return -1;
+
+                if (first != 0)
+                        return first;
+        }
+
+        return strcmp(os1, os2);
+}
+
+static int boot_entry_compare(const void *a, const void *b) {
+        const BootEntry *aa = a;
+        const BootEntry *bb = b;
+
+        return str_verscmp(aa->filename, bb->filename);
+}
+
+int boot_entries_find(const char *dir, BootEntry **entries, size_t *n_entries) {
+        _cleanup_strv_free_ char **files = NULL;
+        char **f;
+        int r;
+
+        BootEntry *array = NULL;
+        size_t n_allocated = 0, n = 0;
+
+        r = conf_files_list(&files, ".conf", NULL, 0, dir, NULL);
+        if (r < 0)
+                return log_error_errno(r, "Failed to list files in \"%s\": %m", dir);
+
+        STRV_FOREACH(f, files) {
+                if (!GREEDY_REALLOC0(array, n_allocated, n + 1))
+                        return log_oom();
+
+                r = boot_entry_load(*f, array + n);
+                if (r < 0)
+                        continue;
+
+                n++;
+        }
+
+        qsort_safe(array, n, sizeof(BootEntry), boot_entry_compare);
+
+        *entries = array;
+        *n_entries = n;
+        return 0;
+}
+
+int boot_entries_select_default(const BootConfig *config) {
+        int i;
+
+        if (config->entry_oneshot)
+                for (i = config->n_entries - 1; i >= 0; i--)
+                        if (streq(config->entry_oneshot, config->entries[i].filename)) {
+                                log_debug("Found default: filename \"%s\" is matched by LoaderEntryOneShot",
+                                          config->entries[i].filename);
+                                return i;
+                        }
+
+        if (config->entry_default)
+                for (i = config->n_entries - 1; i >= 0; i--)
+                        if (streq(config->entry_default, config->entries[i].filename)) {
+                                log_debug("Found default: filename \"%s\" is matched by LoaderEntryDefault",
+                                          config->entries[i].filename);
+                                return i;
+                        }
+
+        if (config->default_pattern)
+                for (i = config->n_entries - 1; i >= 0; i--)
+                        if (fnmatch(config->default_pattern, config->entries[i].filename, FNM_CASEFOLD) == 0) {
+                                log_debug("Found default: filename \"%s\" is matched by pattern \"%s\"",
+                                          config->entries[i].filename, config->default_pattern);
+                                return i;
+                        }
+
+        if (config->n_entries > 0)
+                log_debug("Found default: last entry \"%s\"", config->entries[i].filename);
+        else
+                log_debug("Found no default boot entry :(");
+        return config->n_entries - 1; /* -1 means "no default" */
+}
+
+int boot_entries_load_config(const char *esp_path, BootConfig *config) {
+        const char *p;
+        int r;
+
+        p = strjoina(esp_path, "/loader/loader.conf");
+        r = boot_loader_read_conf(p, config);
+        if (r < 0)
+                return log_error_errno(r, "Failed to read boot config from \"%s\": %m", p);
+
+        p = strjoina(esp_path, "/loader/entries");
+        r = boot_entries_find(p, &config->entries, &config->n_entries);
+        if (r < 0)
+                return log_error_errno(r, "Failed to read boot entries from \"%s\": %m", p);
+
+        r = efi_get_variable_string(EFI_VENDOR_LOADER, "LoaderEntryOneShot", &config->entry_oneshot);
+        if (r < 0 && r != -ENOENT)
+                return log_error_errno(r, "Failed to read EFI var \"LoaderEntryOneShot\": %m");
+
+        r = efi_get_variable_string(EFI_VENDOR_LOADER, "LoaderEntryDefault", &config->entry_default);
+        if (r < 0 && r != -ENOENT)
+                return log_error_errno(r, "Failed to read EFI var \"LoaderEntryDefault\": %m");
+
+        config->default_entry = boot_entries_select_default(config);
+        return 0;
+}
diff --git a/src/shared/bootspec.h b/src/shared/bootspec.h
new file mode 100644
index 0000000000..ff2b90cd32
--- /dev/null
+++ b/src/shared/bootspec.h
@@ -0,0 +1,58 @@
+/***
+  This file is part of systemd.
+
+  Copyright 2017 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 <stdlib.h>
+
+typedef struct BootEntry {
+        char *filename;
+
+        char *title;
+        char *version;
+        char *machine_id;
+        char *architecture;
+        char **options;
+        char *kernel;        /* linux is #defined to 1, yikes! */
+        char *efi;
+        char **initrd;
+        char *device_tree;
+} BootEntry;
+
+typedef struct BootConfig {
+        char *default_pattern;
+        char *timeout;
+        char *editor;
+
+        char *entry_oneshot;
+        char *entry_default;
+
+        BootEntry *entries;
+        size_t n_entries;
+        ssize_t default_entry;
+} BootConfig;
+
+void boot_entry_free(BootEntry *entry);
+int boot_entry_load(const char *path, BootEntry *entry);
+int boot_entries_find(const char *dir, BootEntry **entries, size_t *n_entries);
+int boot_entries_select_default(const BootConfig *config);
+
+int boot_loader_read_conf(const char *path, BootConfig *config);
+void boot_config_free(BootConfig *config);
+int boot_entries_load_config(const char *esp_path, BootConfig *config);
diff --git a/src/shared/meson.build b/src/shared/meson.build
index 883821352e..dfa94cfbdb 100644
--- a/src/shared/meson.build
+++ b/src/shared/meson.build
@@ -10,6 +10,8 @@ shared_sources = '''
         base-filesystem.h
         boot-timestamps.c
         boot-timestamps.h
+        bootspec.c
+        bootspec.h
         bus-unit-util.c
         bus-unit-util.h
         bus-util.c