diff options
| -rw-r--r-- | include/linux/bootconfig.h | 3 | ||||
| -rw-r--r-- | init/main.c | 45 | ||||
| -rw-r--r-- | lib/bootconfig.c | 56 | ||||
| -rw-r--r-- | tools/bootconfig/main.c | 60 |
4 files changed, 111 insertions, 53 deletions
diff --git a/include/linux/bootconfig.h b/include/linux/bootconfig.h index 692a5acc2ffc..1c7f3b74ffcf 100644 --- a/include/linux/bootconfig.h +++ b/include/linux/bootconfig.h @@ -265,6 +265,9 @@ static inline struct xbc_node * __init xbc_node_get_subkey(struct xbc_node *node int __init xbc_node_compose_key_after(struct xbc_node *root, struct xbc_node *node, char *buf, size_t size); +/* Render key/value pairs under @root as a flat cmdline string */ +int __init xbc_snprint_cmdline(char *buf, size_t size, struct xbc_node *root); + /** * xbc_node_compose_key() - Compose full key string of the XBC node * @node: An XBC node. diff --git a/init/main.c b/init/main.c index 96f93bb06c49..e363232b428b 100644 --- a/init/main.c +++ b/init/main.c @@ -324,51 +324,6 @@ static void * __init get_boot_config_from_initrd(size_t *_size) #ifdef CONFIG_BOOT_CONFIG -static char xbc_namebuf[XBC_KEYLEN_MAX] __initdata; - -#define rest(dst, end) ((end) > (dst) ? (end) - (dst) : 0) - -static int __init xbc_snprint_cmdline(char *buf, size_t size, - struct xbc_node *root) -{ - struct xbc_node *knode, *vnode; - char *end = buf + size; - const char *val, *q; - int ret; - - xbc_node_for_each_key_value(root, knode, val) { - ret = xbc_node_compose_key_after(root, knode, - xbc_namebuf, XBC_KEYLEN_MAX); - if (ret < 0) - return ret; - - vnode = xbc_node_get_child(knode); - if (!vnode) { - ret = snprintf(buf, rest(buf, end), "%s ", xbc_namebuf); - if (ret < 0) - return ret; - buf += ret; - continue; - } - xbc_array_for_each_value(vnode, val) { - /* - * For prettier and more readable /proc/cmdline, only - * quote the value when necessary, i.e. when it contains - * whitespace. - */ - q = strpbrk(val, " \t\r\n") ? "\"" : ""; - ret = snprintf(buf, rest(buf, end), "%s=%s%s%s ", - xbc_namebuf, q, val, q); - if (ret < 0) - return ret; - buf += ret; - } - } - - return buf - (end - size); -} -#undef rest - /* Make an extra command line under given key word */ static char * __init xbc_make_cmdline(const char *key) { diff --git a/lib/bootconfig.c b/lib/bootconfig.c index c470b93d5dbc..f445b7703fdd 100644 --- a/lib/bootconfig.c +++ b/lib/bootconfig.c @@ -408,6 +408,62 @@ const char * __init xbc_node_find_next_key_value(struct xbc_node *root, return ""; /* No value key */ } +static char xbc_namebuf[XBC_KEYLEN_MAX] __initdata; + +#define rest(dst, end) ((end) > (dst) ? (end) - (dst) : 0) + +/** + * xbc_snprint_cmdline() - Render bootconfig keys under @root as a cmdline string + * @buf: Destination buffer (may be NULL when @size is 0 to query the length) + * @size: Size of @buf in bytes + * @root: Subtree root whose key=value pairs should be rendered + * + * Walk all key/value pairs under @root and emit them as a space-separated + * cmdline string into @buf. Values containing whitespace are quoted with + * double quotes. Returns the number of bytes that would be written if @buf + * were large enough (matching snprintf semantics), or a negative errno on + * failure. + */ +int __init xbc_snprint_cmdline(char *buf, size_t size, struct xbc_node *root) +{ + struct xbc_node *knode, *vnode; + char *end = buf + size; + const char *val, *q; + int ret; + + xbc_node_for_each_key_value(root, knode, val) { + ret = xbc_node_compose_key_after(root, knode, + xbc_namebuf, XBC_KEYLEN_MAX); + if (ret < 0) + return ret; + + vnode = xbc_node_get_child(knode); + if (!vnode) { + ret = snprintf(buf, rest(buf, end), "%s ", xbc_namebuf); + if (ret < 0) + return ret; + buf += ret; + continue; + } + xbc_array_for_each_value(vnode, val) { + /* + * For prettier and more readable /proc/cmdline, only + * quote the value when necessary, i.e. when it contains + * whitespace. + */ + q = strpbrk(val, " \t\r\n") ? "\"" : ""; + ret = snprintf(buf, rest(buf, end), "%s=%s%s%s ", + xbc_namebuf, q, val, q); + if (ret < 0) + return ret; + buf += ret; + } + } + + return buf - (end - size); +} +#undef rest + /* XBC parse and tree build */ static int __init xbc_init_node(struct xbc_node *node, char *data, uint16_t flag) diff --git a/tools/bootconfig/main.c b/tools/bootconfig/main.c index ddabde20585f..7dc9fff9b637 100644 --- a/tools/bootconfig/main.c +++ b/tools/bootconfig/main.c @@ -286,7 +286,41 @@ static int init_xbc_with_error(char *buf, int len) return ret; } -static int show_xbc(const char *path, bool list) +static int show_xbc_kernel_cmdline(void) +{ + struct xbc_node *root; + char *buf = NULL; + int len, ret; + + root = xbc_find_node("kernel"); + if (!root) + return 0; /* no kernel.* keys: emit empty output */ + + len = xbc_snprint_cmdline(NULL, 0, root); + if (len < 0) { + pr_err("Failed to size cmdline output: %d\n", len); + return len; + } + if (len == 0) + return 0; + + buf = malloc(len + 1); + if (!buf) + return -ENOMEM; + + ret = xbc_snprint_cmdline(buf, len + 1, root); + if (ret < 0) { + pr_err("Failed to render cmdline output: %d\n", ret); + free(buf); + return ret; + } + + fputs(buf, stdout); + free(buf); + return 0; +} + +static int show_xbc(const char *path, bool list, bool render_cmdline) { int ret, fd; char *buf = NULL; @@ -322,11 +356,14 @@ static int show_xbc(const char *path, bool list) if (init_xbc_with_error(buf, ret) < 0) goto out; } - if (list) + if (render_cmdline) + ret = show_xbc_kernel_cmdline(); + else if (list) xbc_show_list(); else xbc_show_compact_tree(); - ret = 0; + if (ret > 0) + ret = 0; out: free(buf); @@ -488,7 +525,10 @@ static int usage(void) " Options:\n" " -a <config>: Apply boot config to initrd\n" " -d : Delete boot config file from initrd\n" - " -l : list boot config in initrd or file\n\n" + " -l : list boot config in initrd or file\n" + " -C : render the kernel.* subtree as a flat cmdline\n" + " string (suitable for embedding in a kernel image)\n" + " and print it to stdout\n\n" " If no option is given, show the bootconfig in the given file.\n"); return -1; } @@ -497,10 +537,11 @@ int main(int argc, char **argv) { char *path = NULL; char *apply = NULL; + bool render_cmdline = false; bool delete = false, list = false; int opt; - while ((opt = getopt(argc, argv, "hda:l")) != -1) { + while ((opt = getopt(argc, argv, "hda:lC")) != -1) { switch (opt) { case 'd': delete = true; @@ -511,14 +552,17 @@ int main(int argc, char **argv) case 'l': list = true; break; + case 'C': + render_cmdline = true; + break; case 'h': default: return usage(); } } - if ((apply && delete) || (delete && list) || (apply && list)) { - pr_err("Error: You can give one of -a, -d or -l at once.\n"); + if ((!!apply + !!delete + !!list + !!render_cmdline) > 1) { + pr_err("Error: You can give one of -a, -d, -l or -C at once.\n"); return usage(); } @@ -534,5 +578,5 @@ int main(int argc, char **argv) else if (delete) return delete_xbc(path); - return show_xbc(path, list); + return show_xbc(path, list, render_cmdline); } |