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authorJason Hobbs <jason.hobbs@calxeda.com>2011-08-31 10:37:30 -0500
committerJohn Rigby <john.rigby@linaro.org>2011-09-23 07:10:39 -0600
commit06b622b246e13ea0d60f47174bfa5c1bb0767002 (patch)
treea9bfabe1c19c3e3c943e82b43b4597114dd0a0c3
parenta0585eaaeeeeee6e3121ce27659086ad9711485c (diff)
downloadu-boot-linaro-stable-06b622b246e13ea0d60f47174bfa5c1bb0767002.tar.gz
Add pxe command
Add pxe command, which is intended to mimic PXELINUX functionality. 'pxe get' uses tftp to retrieve a file based on UUID, MAC address or IP address. 'pxe boot' interprets the contents of PXELINUX config like file to boot using a specific initrd, kernel and kernel command line. This patch also adds a README.pxe file - see it for more details on the pxe command. Signed-off-by: Jason Hobbs <jason.hobbs@calxeda.com>
-rw-r--r--common/Makefile1
-rw-r--r--common/cmd_pxe.c1355
-rw-r--r--common/main.c2
-rw-r--r--doc/README.pxe240
-rw-r--r--include/common.h6
5 files changed, 1604 insertions, 0 deletions
diff --git a/common/Makefile b/common/Makefile
index e3dbcff0f..5663967f1 100644
--- a/common/Makefile
+++ b/common/Makefile
@@ -136,6 +136,7 @@ COBJS-$(CONFIG_CMD_PCI) += cmd_pci.o
endif
COBJS-y += cmd_pcmcia.o
COBJS-$(CONFIG_CMD_PORTIO) += cmd_portio.o
+COBJS-$(CONFIG_CMD_PXE) += cmd_pxe.o
COBJS-$(CONFIG_CMD_REGINFO) += cmd_reginfo.o
COBJS-$(CONFIG_CMD_REISER) += cmd_reiser.o
COBJS-$(CONFIG_CMD_SATA) += cmd_sata.o
diff --git a/common/cmd_pxe.c b/common/cmd_pxe.c
new file mode 100644
index 000000000..3efd7008e
--- /dev/null
+++ b/common/cmd_pxe.c
@@ -0,0 +1,1355 @@
+/*
+ * Copyright 2010-2011 Calxeda, Inc.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the Free
+ * Software Foundation; either version 2 of the License, or (at your option)
+ * any later version.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+#include <common.h>
+#include <command.h>
+#include <malloc.h>
+#include <linux/string.h>
+#include <linux/ctype.h>
+#include <errno.h>
+#include <linux/list.h>
+
+#include "menu.h"
+
+#define MAX_TFTP_PATH_LEN 127
+
+
+/*
+ * Like getenv, but prints an error if envvar isn't defined in the
+ * environment. It always returns what getenv does, so it can be used in
+ * place of getenv without changing error handling otherwise.
+ */
+static char *from_env(char *envvar)
+{
+ char *ret;
+
+ ret = getenv(envvar);
+
+ if (!ret)
+ printf("missing environment variable: %s\n", envvar);
+
+ return ret;
+}
+
+/*
+ * Convert an ethaddr from the environment to the format used by pxelinux
+ * filenames based on mac addresses. Convert's ':' to '-', and adds "01-" to
+ * the beginning of the ethernet address to indicate a hardware type of
+ * Ethernet. Also converts uppercase hex characters into lowercase, to match
+ * pxelinux's behavior.
+ *
+ * Returns 1 for success, -ENOENT if 'ethaddr' is undefined in the
+ * environment, or some other value < 0 on error.
+ */
+static int format_mac_pxe(char *outbuf, size_t outbuf_len)
+{
+ size_t ethaddr_len;
+ char *p, *ethaddr;
+
+ ethaddr = from_env("ethaddr");
+
+ if (!ethaddr)
+ return -ENOENT;
+
+ ethaddr_len = strlen(ethaddr);
+
+ /*
+ * ethaddr_len + 4 gives room for "01-", ethaddr, and a NUL byte at
+ * the end.
+ */
+ if (outbuf_len < ethaddr_len + 4) {
+ printf("outbuf is too small (%d < %d)\n",
+ outbuf_len, ethaddr_len + 4);
+
+ return -EINVAL;
+ }
+
+ strcpy(outbuf, "01-");
+
+ for (p = outbuf + 3; *ethaddr; ethaddr++, p++) {
+ if (*ethaddr == ':')
+ *p = '-';
+ else
+ *p = tolower(*ethaddr);
+ }
+
+ *p = '\0';
+
+ return 1;
+}
+
+/*
+ * Returns the directory the file specified in the bootfile env variable is
+ * in. If bootfile isn't defined in the environment, return NULL, which should
+ * be interpreted as "don't prepend anything to paths".
+ */
+static int get_bootfile_path(char *bootfile_path, size_t bootfile_path_size)
+{
+ char *bootfile, *last_slash;
+ size_t path_len;
+
+ bootfile = from_env("bootfile");
+
+ if (!bootfile) {
+ bootfile_path[0] = '\0';
+ return 1;
+ }
+
+ last_slash = strrchr(bootfile, '/');
+
+ if (last_slash == NULL) {
+ bootfile_path[0] = '\0';
+ return 1;
+ }
+
+ path_len = (last_slash - bootfile) + 1;
+
+ if (bootfile_path_size < path_len) {
+ printf("bootfile_path too small. (%d < %d)\n",
+ bootfile_path_size, path_len);
+
+ return -1;
+ }
+
+ strncpy(bootfile_path, bootfile, path_len);
+
+ bootfile_path[path_len] = '\0';
+
+ return 1;
+}
+
+/*
+ * As in pxelinux, paths to files referenced from files we retrieve are
+ * relative to the location of bootfile. get_relfile takes such a path and
+ * joins it with the bootfile path to get the full path to the target file. If
+ * the bootfile path is NULL, we use file_path as is.
+ *
+ * Returns 1 for success, or < 0 on error.
+ */
+static int get_relfile(char *file_path, void *file_addr)
+{
+ size_t path_len;
+ char relfile[MAX_TFTP_PATH_LEN+1];
+ char addr_buf[10];
+ char *tftp_argv[] = {"tftp", NULL, NULL, NULL};
+ int err;
+
+ err = get_bootfile_path(relfile, sizeof(relfile));
+
+ if (err < 0)
+ return err;
+
+ path_len = strlen(file_path);
+ path_len += strlen(relfile);
+
+ if (path_len > MAX_TFTP_PATH_LEN) {
+ printf("Base path too long (%s%s)\n",
+ relfile,
+ file_path);
+
+ return -ENAMETOOLONG;
+ }
+
+ strcat(relfile, file_path);
+
+ printf("Retrieving file: %s\n", relfile);
+
+ sprintf(addr_buf, "%p", file_addr);
+
+ tftp_argv[1] = addr_buf;
+ tftp_argv[2] = relfile;
+
+ if (do_tftpb(NULL, 0, 3, tftp_argv))
+ return -ENOENT;
+
+ return 1;
+}
+
+/*
+ * Retrieve the file at 'file_path' to the locate given by 'file_addr'. If
+ * 'bootfile' was specified in the environment, the path to bootfile will be
+ * prepended to 'file_path' and the resulting path will be used.
+ *
+ * Returns 1 on success, or < 0 for error.
+ */
+static int get_pxe_file(char *file_path, void *file_addr)
+{
+ unsigned long config_file_size;
+ char *tftp_filesize;
+ int err;
+
+ err = get_relfile(file_path, file_addr);
+
+ if (err < 0)
+ return err;
+
+ /*
+ * the file comes without a NUL byte at the end, so find out its size
+ * and add the NUL byte.
+ */
+ tftp_filesize = from_env("filesize");
+
+ if (!tftp_filesize)
+ return -ENOENT;
+
+ if (strict_strtoul(tftp_filesize, 16, &config_file_size) < 0)
+ return -EINVAL;
+
+ *(char *)(file_addr + config_file_size) = '\0';
+
+ return 1;
+}
+
+#define PXELINUX_DIR "pxelinux.cfg/"
+
+/*
+ * Retrieves a file in the 'pxelinux.cfg' folder. Since this uses get_pxe_file
+ * to do the hard work, the location of the 'pxelinux.cfg' folder is generated
+ * from the bootfile path, as described above.
+ *
+ * Returns 1 on success or < 0 on error.
+ */
+static int get_pxelinux_path(char *file, void *pxefile_addr_r)
+{
+ size_t base_len = strlen(PXELINUX_DIR);
+ char path[MAX_TFTP_PATH_LEN+1];
+
+ if (base_len + strlen(file) > MAX_TFTP_PATH_LEN) {
+ printf("path (%s%s) too long, skipping\n",
+ PXELINUX_DIR, file);
+ return -ENAMETOOLONG;
+ }
+
+ sprintf(path, PXELINUX_DIR "%s", file);
+
+ return get_pxe_file(path, pxefile_addr_r);
+}
+
+/*
+ * Looks for a pxe file with a name based on the pxeuuid environment variable.
+ *
+ * Returns 1 on success or < 0 on error.
+ */
+static int pxe_uuid_path(void *pxefile_addr_r)
+{
+ char *uuid_str;
+
+ uuid_str = from_env("pxeuuid");
+
+ if (!uuid_str)
+ return -ENOENT;
+
+ return get_pxelinux_path(uuid_str, pxefile_addr_r);
+}
+
+/*
+ * Looks for a pxe file with a name based on the 'ethaddr' environment
+ * variable.
+ *
+ * Returns 1 on success or < 0 on error.
+ */
+static int pxe_mac_path(void *pxefile_addr_r)
+{
+ char mac_str[21];
+ int err;
+
+ err = format_mac_pxe(mac_str, sizeof(mac_str));
+
+ if (err < 0)
+ return err;
+
+ return get_pxelinux_path(mac_str, pxefile_addr_r);
+}
+
+/*
+ * Looks for pxe files with names based on our IP address. See pxelinux
+ * documentation for details on what these file names look like. We match
+ * that exactly.
+ *
+ * Returns 1 on success or < 0 on error.
+ */
+static int pxe_ipaddr_paths(void *pxefile_addr_r)
+{
+ char ip_addr[9];
+ int mask_pos, err;
+
+ sprintf(ip_addr, "%08X", ntohl(NetOurIP));
+
+ for (mask_pos = 7; mask_pos >= 0; mask_pos--) {
+ err = get_pxelinux_path(ip_addr, pxefile_addr_r);
+
+ if (err > 0)
+ return err;
+
+ ip_addr[mask_pos] = '\0';
+ }
+
+ return -ENOENT;
+}
+
+/*
+ * Entry point for the 'pxe get' command.
+ * This Follows pxelinux's rules to download a config file from a tftp server.
+ * The file is stored at the location given by the pxefile_addr_r environment
+ * variable, which must be set.
+ *
+ * UUID comes from pxeuuid env variable, if defined
+ * MAC addr comes from ethaddr env variable, if defined
+ * IP
+ *
+ * see http://syslinux.zytor.com/wiki/index.php/PXELINUX
+ *
+ * Returns 0 on success or 1 on error.
+ */
+static int
+do_pxe_get(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
+{
+ char *pxefile_addr_str;
+ void *pxefile_addr_r;
+ int err;
+
+ if (argc != 1)
+ return cmd_usage(cmdtp);
+
+
+ pxefile_addr_str = from_env("pxefile_addr_r");
+
+ if (!pxefile_addr_str)
+ return 1;
+
+ err = strict_strtoul(pxefile_addr_str, 16,
+ (unsigned long *)&pxefile_addr_r);
+ if (err < 0)
+ return 1;
+
+ /*
+ * Keep trying paths until we successfully get a file we're looking
+ * for.
+ */
+ if (pxe_uuid_path(pxefile_addr_r) > 0
+ || pxe_mac_path(pxefile_addr_r) > 0
+ || pxe_ipaddr_paths(pxefile_addr_r) > 0
+ || get_pxelinux_path("default", pxefile_addr_r) > 0) {
+
+ printf("Config file found\n");
+
+ return 0;
+ }
+
+ printf("Config file not found\n");
+
+ return 1;
+}
+
+/*
+ * Wrapper to make it easier to store the file at file_path in the location
+ * specified by envaddr_name. file_path will be joined to the bootfile path,
+ * if any is specified.
+ *
+ * Returns 1 on success or < 0 on error.
+ */
+static int get_relfile_envaddr(char *file_path, char *envaddr_name)
+{
+ void *file_addr;
+ char *envaddr;
+
+ envaddr = from_env(envaddr_name);
+
+ if (!envaddr)
+ return -ENOENT;
+
+ if (strict_strtoul(envaddr, 16, (unsigned long *)&file_addr) < 0)
+ return -EINVAL;
+
+ return get_relfile(file_path, file_addr);
+}
+
+/*
+ * A note on the pxe file parser.
+ *
+ * We're parsing files that use syslinux grammar, which has a few quirks.
+ * String literals must be recognized based on context - there is no
+ * quoting or escaping support. There's also nothing to explicitly indicate
+ * when a label section completes. We deal with that by ending a label
+ * section whenever we see a line that doesn't include.
+ *
+ * As with the syslinux family, this same file format could be reused in the
+ * future for non pxe purposes. The only action it takes during parsing that
+ * would throw this off is handling of include files. It assumes we're using
+ * pxe, and does a tftp download of a file listed as an include file in the
+ * middle of the parsing operation. That could be handled by refactoring it to
+ * take a 'include file getter' function.
+ */
+
+/*
+ * Describes a single label given in a pxe file.
+ *
+ * Create these with the 'label_create' function given below.
+ *
+ * name - the name of the menu as given on the 'menu label' line.
+ * kernel - the path to the kernel file to use for this label.
+ * append - kernel command line to use when booting this label
+ * initrd - path to the initrd to use for this label.
+ * attempted - 0 if we haven't tried to boot this label, 1 if we have.
+ * localboot - 1 if this label specified 'localboot', 0 otherwise.
+ * list - lets these form a list, which a pxe_menu struct will hold.
+ */
+struct pxe_label {
+ char *name;
+ char *kernel;
+ char *append;
+ char *initrd;
+ int attempted;
+ int localboot;
+ struct list_head list;
+};
+
+/*
+ * Describes a pxe menu as given via pxe files.
+ *
+ * title - the name of the menu as given by a 'menu title' line.
+ * default_label - the name of the default label, if any.
+ * timeout - time in tenths of a second to wait for a user key-press before
+ * booting the default label.
+ * prompt - if 0, don't prompt for a choice unless the timeout period is
+ * interrupted. If 1, always prompt for a choice regardless of
+ * timeout.
+ * labels - a list of labels defined for the menu.
+ */
+struct pxe_menu {
+ char *title;
+ char *default_label;
+ int timeout;
+ int prompt;
+ struct list_head labels;
+};
+
+/*
+ * Allocates memory for and initializes a pxe_label. This uses malloc, so the
+ * result must be free()'d to reclaim the memory.
+ *
+ * Returns NULL if malloc fails.
+ */
+static struct pxe_label *label_create(void)
+{
+ struct pxe_label *label;
+
+ label = malloc(sizeof(struct pxe_label));
+
+ if (!label)
+ return NULL;
+
+ memset(label, 0, sizeof(struct pxe_label));
+
+ return label;
+}
+
+/*
+ * Free the memory used by a pxe_label, including that used by its name,
+ * kernel, append and initrd members, if they're non NULL.
+ *
+ * So - be sure to only use dynamically allocated memory for the members of
+ * the pxe_label struct, unless you want to clean it up first. These are
+ * currently only created by the pxe file parsing code.
+ */
+static void label_destroy(struct pxe_label *label)
+{
+ if (label->name)
+ free(label->name);
+
+ if (label->kernel)
+ free(label->kernel);
+
+ if (label->append)
+ free(label->append);
+
+ if (label->initrd)
+ free(label->initrd);
+
+ free(label);
+}
+
+/*
+ * Print a label and its string members if they're defined.
+ *
+ * This is passed as a callback to the menu code for displaying each
+ * menu entry.
+ */
+static void label_print(void *data)
+{
+ struct pxe_label *label = data;
+
+ printf("Label: %s\n", label->name);
+
+ if (label->kernel)
+ printf("\tkernel: %s\n", label->kernel);
+
+ if (label->append)
+ printf("\tappend: %s\n", label->append);
+
+ if (label->initrd)
+ printf("\tinitrd: %s\n", label->initrd);
+}
+
+/*
+ * Boot a label that specified 'localboot'. This requires that the 'localcmd'
+ * environment variable is defined. Its contents will be executed as U-boot
+ * command. If the label specified an 'append' line, its contents will be
+ * used to overwrite the contents of the 'bootargs' environment variable prior
+ * to running 'localcmd'.
+ *
+ * Returns 1 on success or < 0 on error.
+ */
+static int label_localboot(struct pxe_label *label)
+{
+ char *localcmd, *dupcmd;
+ int ret;
+
+ localcmd = from_env("localcmd");
+
+ if (!localcmd)
+ return -ENOENT;
+
+ /*
+ * dup the command to avoid any issues with the version of it existing
+ * in the environment changing during the execution of the command.
+ */
+ dupcmd = strdup(localcmd);
+
+ if (!dupcmd)
+ return -ENOMEM;
+
+ if (label->append)
+ setenv("bootargs", label->append);
+
+ printf("running: %s\n", dupcmd);
+
+ ret = run_command2(dupcmd, 0);
+
+ free(dupcmd);
+
+ return ret;
+}
+
+/*
+ * Boot according to the contents of a pxe_label.
+ *
+ * If we can't boot for any reason, we return. A successful boot never
+ * returns.
+ *
+ * The kernel will be stored in the location given by the 'kernel_addr_r'
+ * environment variable.
+ *
+ * If the label specifies an initrd file, it will be stored in the location
+ * given by the 'ramdisk_addr_r' environment variable.
+ *
+ * If the label specifies an 'append' line, its contents will overwrite that
+ * of the 'bootargs' environment variable.
+ */
+static void label_boot(struct pxe_label *label)
+{
+ char *bootm_argv[] = { "bootm", NULL, NULL, NULL, NULL };
+ int bootm_argc = 3;
+
+ label_print(label);
+
+ label->attempted = 1;
+
+ if (label->localboot) {
+ label_localboot(label);
+ return;
+ }
+
+ if (label->kernel == NULL) {
+ printf("No kernel given, skipping %s\n",
+ label->name);
+ return;
+ }
+
+ if (label->initrd) {
+ if (get_relfile_envaddr(label->initrd, "ramdisk_addr_r") < 0) {
+ printf("Skipping %s for failure retrieving initrd\n",
+ label->name);
+ return;
+ }
+
+ bootm_argv[2] = getenv("ramdisk_addr_r");
+ } else {
+ bootm_argv[2] = "-";
+ }
+
+ if (get_relfile_envaddr(label->kernel, "kernel_addr_r") < 0) {
+ printf("Skipping %s for failure retrieving kernel\n",
+ label->name);
+ return;
+ }
+
+ if (label->append)
+ setenv("bootargs", label->append);
+
+ bootm_argv[1] = getenv("kernel_addr_r");
+
+ /*
+ * fdt usage is optional. If there is an fdt_addr specified, we will
+ * pass it along to bootm, and adjust argc appropriately.
+ */
+ bootm_argv[3] = getenv("fdt_addr");
+
+ if (bootm_argv[3])
+ bootm_argc = 4;
+
+ do_bootm(NULL, 0, bootm_argc, bootm_argv);
+}
+
+/*
+ * Tokens for the pxe file parser.
+ */
+enum token_type {
+ T_EOL,
+ T_STRING,
+ T_EOF,
+ T_MENU,
+ T_TITLE,
+ T_TIMEOUT,
+ T_LABEL,
+ T_KERNEL,
+ T_APPEND,
+ T_INITRD,
+ T_LOCALBOOT,
+ T_DEFAULT,
+ T_PROMPT,
+ T_INCLUDE,
+ T_INVALID
+};
+
+/*
+ * A token - given by a value and a type.
+ */
+struct token {
+ char *val;
+ enum token_type type;
+};
+
+/*
+ * Keywords recognized.
+ */
+static const struct token keywords[] = {
+ {"menu", T_MENU},
+ {"title", T_TITLE},
+ {"timeout", T_TIMEOUT},
+ {"default", T_DEFAULT},
+ {"prompt", T_PROMPT},
+ {"label", T_LABEL},
+ {"kernel", T_KERNEL},
+ {"localboot", T_LOCALBOOT},
+ {"append", T_APPEND},
+ {"initrd", T_INITRD},
+ {"include", T_INCLUDE},
+ {NULL, T_INVALID}
+};
+
+/*
+ * Since pxe(linux) files don't have a token to identify the start of a
+ * literal, we have to keep track of when we're in a state where a literal is
+ * expected vs when we're in a state a keyword is expected.
+ */
+enum lex_state {
+ L_NORMAL = 0,
+ L_KEYWORD,
+ L_SLITERAL
+};
+
+/*
+ * get_string retrieves a string from *p and stores it as a token in
+ * *t.
+ *
+ * get_string used for scanning both string literals and keywords.
+ *
+ * Characters from *p are copied into t-val until a character equal to
+ * delim is found, or a NUL byte is reached. If delim has the special value of
+ * ' ', any whitespace character will be used as a delimiter.
+ *
+ * If lower is unequal to 0, uppercase characters will be converted to
+ * lowercase in the result. This is useful to make keywords case
+ * insensitive.
+ *
+ * The location of *p is updated to point to the first character after the end
+ * of the token - the ending delimiter.
+ *
+ * On success, the new value of t->val is returned. Memory for t->val is
+ * allocated using malloc and must be free()'d to reclaim it. If insufficient
+ * memory is available, NULL is returned.
+ */
+static char *get_string(char **p, struct token *t, char delim, int lower)
+{
+ char *b, *e;
+ size_t len, i;
+
+ /*
+ * b and e both start at the beginning of the input stream.
+ *
+ * e is incremented until we find the ending delimiter, or a NUL byte
+ * is reached. Then, we take e - b to find the length of the token.
+ */
+ b = e = *p;
+
+ while (*e) {
+ if ((delim == ' ' && isspace(*e)) || delim == *e)
+ break;
+ e++;
+ }
+
+ len = e - b;
+
+ /*
+ * Allocate memory to hold the string, and copy it in, converting
+ * characters to lowercase if lower is != 0.
+ */
+ t->val = malloc(len + 1);
+ if (!t->val)
+ return NULL;
+
+ for (i = 0; i < len; i++, b++) {
+ if (lower)
+ t->val[i] = tolower(*b);
+ else
+ t->val[i] = *b;
+ }
+
+ t->val[len] = '\0';
+
+ /*
+ * Update *p so the caller knows where to continue scanning.
+ */
+ *p = e;
+
+ t->type = T_STRING;
+
+ return t->val;
+}
+
+/*
+ * Populate a keyword token with a type and value.
+ */
+static void get_keyword(struct token *t)
+{
+ int i;
+
+ for (i = 0; keywords[i].val; i++) {
+ if (!strcmp(t->val, keywords[i].val)) {
+ t->type = keywords[i].type;
+ break;
+ }
+ }
+}
+
+/*
+ * Get the next token. We have to keep track of which state we're in to know
+ * if we're looking to get a string literal or a keyword.
+ *
+ * *p is updated to point at the first character after the current token.
+ */
+static void get_token(char **p, struct token *t, enum lex_state state)
+{
+ char *c = *p;
+
+ t->type = T_INVALID;
+
+ /* eat non EOL whitespace */
+ while (isblank(*c))
+ c++;
+
+ /*
+ * eat comments. note that string literals can't begin with #, but
+ * can contain a # after their first character.
+ */
+ if (*c == '#') {
+ while (*c && *c != '\n')
+ c++;
+ }
+
+ if (*c == '\n') {
+ t->type = T_EOL;
+ c++;
+ } else if (*c == '\0') {
+ t->type = T_EOF;
+ c++;
+ } else if (state == L_SLITERAL) {
+ get_string(&c, t, '\n', 0);
+ } else if (state == L_KEYWORD) {
+ /*
+ * when we expect a keyword, we first get the next string
+ * token delimited by whitespace, and then check if it
+ * matches a keyword in our keyword list. if it does, it's
+ * converted to a keyword token of the appropriate type, and
+ * if not, it remains a string token.
+ */
+ get_string(&c, t, ' ', 1);
+ get_keyword(t);
+ }
+
+ *p = c;
+}
+
+/*
+ * Increment *c until we get to the end of the current line, or EOF.
+ */
+static void eol_or_eof(char **c)
+{
+ while (**c && **c != '\n')
+ (*c)++;
+}
+
+/*
+ * All of these parse_* functions share some common behavior.
+ *
+ * They finish with *c pointing after the token they parse, and return 1 on
+ * success, or < 0 on error.
+ */
+
+/*
+ * Parse a string literal and store a pointer it at *dst. String literals
+ * terminate at the end of the line.
+ */
+static int parse_sliteral(char **c, char **dst)
+{
+ struct token t;
+ char *s = *c;
+
+ get_token(c, &t, L_SLITERAL);
+
+ if (t.type != T_STRING) {
+ printf("Expected string literal: %.*s\n", (int)(*c - s), s);
+ return -EINVAL;
+ }
+
+ *dst = t.val;
+
+ return 1;
+}
+
+/*
+ * Parse a base 10 (unsigned) integer and store it at *dst.
+ */
+static int parse_integer(char **c, int *dst)
+{
+ struct token t;
+ char *s = *c;
+ unsigned long temp;
+
+ get_token(c, &t, L_SLITERAL);
+
+ if (t.type != T_STRING) {
+ printf("Expected string: %.*s\n", (int)(*c - s), s);
+ return -EINVAL;
+ }
+
+ if (strict_strtoul(t.val, 10, &temp) < 0) {
+ printf("Expected unsigned integer: %s\n", t.val);
+ return -EINVAL;
+ }
+
+ *dst = (int)temp;
+
+ free(t.val);
+
+ return 1;
+}
+
+static int parse_pxefile_top(char *p, struct pxe_menu *cfg, int nest_level);
+
+/*
+ * Parse an include statement, and retrieve and parse the file it mentions.
+ *
+ * base should point to a location where it's safe to store the file, and
+ * nest_level should indicate how many nested includes have occurred. For this
+ * include, nest_level has already been incremented and doesn't need to be
+ * incremented here.
+ */
+static int handle_include(char **c, char *base,
+ struct pxe_menu *cfg, int nest_level)
+{
+ char *include_path;
+ char *s = *c;
+ int err;
+
+ err = parse_sliteral(c, &include_path);
+
+ if (err < 0) {
+ printf("Expected include path: %.*s\n",
+ (int)(*c - s), s);
+ return err;
+ }
+
+ err = get_pxe_file(include_path, base);
+
+ if (err < 0) {
+ printf("Couldn't retrieve %s\n", include_path);
+ return err;
+ }
+
+ return parse_pxefile_top(base, cfg, nest_level);
+}
+
+/*
+ * Parse lines that begin with 'menu'.
+ *
+ * b and nest are provided to handle the 'menu include' case.
+ *
+ * b should be the address where the file currently being parsed is stored.
+ *
+ * nest_level should be 1 when parsing the top level pxe file, 2 when parsing
+ * a file it includes, 3 when parsing a file included by that file, and so on.
+ */
+static int parse_menu(char **c, struct pxe_menu *cfg, char *b, int nest_level)
+{
+ struct token t;
+ char *s = *c;
+ int err;
+
+ get_token(c, &t, L_KEYWORD);
+
+ switch (t.type) {
+ case T_TITLE:
+ err = parse_sliteral(c, &cfg->title);
+
+ break;
+
+ case T_INCLUDE:
+ err = handle_include(c, b + strlen(b) + 1, cfg,
+ nest_level + 1);
+ break;
+
+ default:
+ printf("Ignoring malformed menu command: %.*s\n",
+ (int)(*c - s), s);
+ }
+
+ if (err < 0)
+ return err;
+
+ eol_or_eof(c);
+
+ return 1;
+}
+
+/*
+ * Handles parsing a 'menu line' when we're parsing a label.
+ */
+static int parse_label_menu(char **c, struct pxe_menu *cfg,
+ struct pxe_label *label)
+{
+ struct token t;
+ char *s;
+
+ s = *c;
+
+ get_token(c, &t, L_KEYWORD);
+
+ switch (t.type) {
+ case T_DEFAULT:
+ if (cfg->default_label)
+ free(cfg->default_label);
+
+ cfg->default_label = strdup(label->name);
+
+ if (!cfg->default_label)
+ return -ENOMEM;
+
+ break;
+ default:
+ printf("Ignoring malformed menu command: %.*s\n",
+ (int)(*c - s), s);
+ }
+
+ eol_or_eof(c);
+
+ return 0;
+}
+
+/*
+ * Parses a label and adds it to the list of labels for a menu.
+ *
+ * A label ends when we either get to the end of a file, or
+ * get some input we otherwise don't have a handler defined
+ * for.
+ *
+ */
+static int parse_label(char **c, struct pxe_menu *cfg)
+{
+ struct token t;
+ char *s = *c;
+ struct pxe_label *label;
+ int err;
+
+ label = label_create();
+ if (!label)
+ return -ENOMEM;
+
+ err = parse_sliteral(c, &label->name);
+ if (err < 0) {
+ printf("Expected label name: %.*s\n", (int)(*c - s), s);
+ label_destroy(label);
+ return -EINVAL;
+ }
+
+ list_add_tail(&label->list, &cfg->labels);
+
+ while (1) {
+ s = *c;
+ get_token(c, &t, L_KEYWORD);
+
+ err = 0;
+ switch (t.type) {
+ case T_MENU:
+ err = parse_label_menu(c, cfg, label);
+ break;
+
+ case T_KERNEL:
+ err = parse_sliteral(c, &label->kernel);
+ break;
+
+ case T_APPEND:
+ err = parse_sliteral(c, &label->append);
+ break;
+
+ case T_INITRD:
+ err = parse_sliteral(c, &label->initrd);
+ break;
+
+ case T_LOCALBOOT:
+ err = parse_integer(c, &label->localboot);
+ break;
+
+ case T_EOL:
+ break;
+
+ default:
+ /*
+ * put the token back! we don't want it - it's the end
+ * of a label and whatever token this is, it's
+ * something for the menu level context to handle.
+ */
+ *c = s;
+ return 1;
+ }
+
+ if (err < 0)
+ return err;
+ }
+}
+
+/*
+ * This 16 comes from the limit pxelinux imposes on nested includes.
+ *
+ * There is no reason at all we couldn't do more, but some limit helps prevent
+ * infinite (until crash occurs) recursion if a file tries to include itself.
+ */
+#define MAX_NEST_LEVEL 16
+
+/*
+ * Entry point for parsing a menu file. nest_level indicates how many times
+ * we've nested in includes. It will be 1 for the top level menu file.
+ *
+ * Returns 1 on success, < 0 on error.
+ */
+static int parse_pxefile_top(char *p, struct pxe_menu *cfg, int nest_level)
+{
+ struct token t;
+ char *s, *b, *label_name;
+ int err;
+
+ b = p;
+
+ if (nest_level > MAX_NEST_LEVEL) {
+ printf("Maximum nesting (%d) exceeded\n", MAX_NEST_LEVEL);
+ return -EMLINK;
+ }
+
+ while (1) {
+ s = p;
+
+ get_token(&p, &t, L_KEYWORD);
+
+ err = 0;
+ switch (t.type) {
+ case T_MENU:
+ err = parse_menu(&p, cfg, b, nest_level);
+ break;
+
+ case T_TIMEOUT:
+ err = parse_integer(&p, &cfg->timeout);
+ break;
+
+ case T_LABEL:
+ err = parse_label(&p, cfg);
+ break;
+
+ case T_DEFAULT:
+ err = parse_sliteral(&p, &label_name);
+
+ if (label_name) {
+ if (cfg->default_label)
+ free(cfg->default_label);
+
+ cfg->default_label = label_name;
+ }
+
+ break;
+
+ case T_PROMPT:
+ err = parse_integer(&p, &cfg->prompt);
+ break;
+
+ case T_EOL:
+ break;
+
+ case T_EOF:
+ return 1;
+
+ default:
+ printf("Ignoring unknown command: %.*s\n",
+ (int)(p - s), s);
+ eol_or_eof(&p);
+ }
+
+ if (err < 0)
+ return err;
+ }
+}
+
+/*
+ * Free the memory used by a pxe_menu and its labels.
+ */
+static void destroy_pxe_menu(struct pxe_menu *cfg)
+{
+ struct list_head *pos, *n;
+ struct pxe_label *label;
+
+ if (cfg->title)
+ free(cfg->title);
+
+ if (cfg->default_label)
+ free(cfg->default_label);
+
+ list_for_each_safe(pos, n, &cfg->labels) {
+ label = list_entry(pos, struct pxe_label, list);
+
+ label_destroy(label);
+ }
+
+ free(cfg);
+}
+
+/*
+ * Entry point for parsing a pxe file. This is only used for the top level
+ * file.
+ *
+ * Returns NULL if there is an error, otherwise, returns a pointer to a
+ * pxe_menu struct populated with the results of parsing the pxe file (and any
+ * files it includes). The resulting pxe_menu struct can be free()'d by using
+ * the destroy_pxe_menu() function.
+ */
+static struct pxe_menu *parse_pxefile(char *menucfg)
+{
+ struct pxe_menu *cfg;
+
+ cfg = malloc(sizeof(struct pxe_menu));
+
+ if (!cfg)
+ return NULL;
+
+ memset(cfg, 0, sizeof(struct pxe_menu));
+
+ INIT_LIST_HEAD(&cfg->labels);
+
+ if (parse_pxefile_top(menucfg, cfg, 1) < 0) {
+ destroy_pxe_menu(cfg);
+ return NULL;
+ }
+
+ return cfg;
+}
+
+/*
+ * Converts a pxe_menu struct into a menu struct for use with U-boot's generic
+ * menu code.
+ */
+static struct menu *pxe_menu_to_menu(struct pxe_menu *cfg)
+{
+ struct pxe_label *label;
+ struct list_head *pos;
+ struct menu *m;
+ int err;
+
+ /*
+ * Create a menu and add items for all the labels.
+ */
+ m = menu_create(cfg->title, cfg->timeout, cfg->prompt, label_print);
+
+ if (!m)
+ return NULL;
+
+ list_for_each(pos, &cfg->labels) {
+ label = list_entry(pos, struct pxe_label, list);
+
+ if (menu_item_add(m, label->name, label) != 1) {
+ menu_destroy(m);
+ return NULL;
+ }
+ }
+
+ /*
+ * After we've created items for each label in the menu, set the
+ * menu's default label if one was specified.
+ */
+ if (cfg->default_label) {
+ err = menu_default_set(m, cfg->default_label);
+ if (err != 1) {
+ if (err != -ENOENT) {
+ menu_destroy(m);
+ return NULL;
+ }
+
+ printf("Missing default: %s\n", cfg->default_label);
+ }
+ }
+
+ return m;
+}
+
+/*
+ * Try to boot any labels we have yet to attempt to boot.
+ */
+static void boot_unattempted_labels(struct pxe_menu *cfg)
+{
+ struct list_head *pos;
+ struct pxe_label *label;
+
+ list_for_each(pos, &cfg->labels) {
+ label = list_entry(pos, struct pxe_label, list);
+
+ if (!label->attempted)
+ label_boot(label);
+ }
+}
+
+/*
+ * Boot the system as prescribed by a pxe_menu.
+ *
+ * Use the menu system to either get the user's choice or the default, based
+ * on config or user input. If there is no default or user's choice,
+ * attempted to boot labels in the order they were given in pxe files.
+ * If the default or user's choice fails to boot, attempt to boot other
+ * labels in the order they were given in pxe files.
+ *
+ * If this function returns, there weren't any labels that successfully
+ * booted, or the user interrupted the menu selection via ctrl+c.
+ */
+static void handle_pxe_menu(struct pxe_menu *cfg)
+{
+ void *choice;
+ struct menu *m;
+ int err;
+
+ m = pxe_menu_to_menu(cfg);
+ if (!m)
+ return;
+
+ err = menu_get_choice(m, &choice);
+
+ menu_destroy(m);
+
+ if (err < 1)
+ return;
+
+ label_boot(choice);
+
+ boot_unattempted_labels(cfg);
+}
+
+/*
+ * Boots a system using a pxe file
+ *
+ * Returns 0 on success, 1 on error.
+ */
+static int
+do_pxe_boot(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
+{
+ unsigned long pxefile_addr_r;
+ struct pxe_menu *cfg;
+ char *pxefile_addr_str;
+
+ if (argc == 1) {
+ pxefile_addr_str = from_env("pxefile_addr_r");
+ if (!pxefile_addr_str)
+ return 1;
+
+ } else if (argc == 2) {
+ pxefile_addr_str = argv[1];
+ } else {
+ return cmd_usage(cmdtp);
+ }
+
+ if (strict_strtoul(pxefile_addr_str, 16, &pxefile_addr_r) < 0) {
+ printf("Invalid pxefile address: %s\n", pxefile_addr_str);
+ return 1;
+ }
+
+ cfg = parse_pxefile((char *)(pxefile_addr_r));
+
+ if (cfg == NULL) {
+ printf("Error parsing config file\n");
+ return 1;
+ }
+
+ handle_pxe_menu(cfg);
+
+ destroy_pxe_menu(cfg);
+
+ return 0;
+}
+
+static cmd_tbl_t cmd_pxe_sub[] = {
+ U_BOOT_CMD_MKENT(get, 1, 1, do_pxe_get, "", ""),
+ U_BOOT_CMD_MKENT(boot, 2, 1, do_pxe_boot, "", "")
+};
+
+int do_pxe(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
+{
+ cmd_tbl_t *cp;
+
+ if (argc < 2)
+ return cmd_usage(cmdtp);
+
+ /* drop initial "pxe" arg */
+ argc--;
+ argv++;
+
+ cp = find_cmd_tbl(argv[0], cmd_pxe_sub, ARRAY_SIZE(cmd_pxe_sub));
+
+ if (cp)
+ return cp->cmd(cmdtp, flag, argc, argv);
+
+ return cmd_usage(cmdtp);
+}
+
+U_BOOT_CMD(
+ pxe, 3, 1, do_pxe,
+ "commands to get and boot from pxe files",
+ "get - try to retrieve a pxe file using tftp\npxe "
+ "boot [pxefile_addr_r] - boot from the pxe file at pxefile_addr_r\n"
+);
diff --git a/common/main.c b/common/main.c
index 7be295528..e96c95a03 100644
--- a/common/main.c
+++ b/common/main.c
@@ -269,7 +269,9 @@ int abortboot(int bootdelay)
/*
* Return 0 on success, or != 0 on error.
*/
+#ifndef CONFIG_CMD_PXE
static inline
+#endif
int run_command2(const char *cmd, int flag)
{
#ifndef CONFIG_SYS_HUSH_PARSER
diff --git a/doc/README.pxe b/doc/README.pxe
new file mode 100644
index 000000000..9026d9c9d
--- /dev/null
+++ b/doc/README.pxe
@@ -0,0 +1,240 @@
+/*
+ * Copyright 2010-2011 Calxeda, Inc.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the Free
+ * Software Foundation; either version 2 of the License, or (at your option)
+ * any later version.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+The 'pxe' commands provide a near subset of the functionality provided by
+the PXELINUX boot loader. This allows U-boot based systems to be controlled
+remotely using the same PXE based techniques that many non U-boot based servers
+use.
+
+Commands
+========
+
+pxe get
+-------
+ syntax: pxe get
+
+ follows PXELINUX's rules for retrieving configuration files from a tftp
+ server, and supports a subset of PXELINUX's config file syntax.
+
+ Environment
+ -----------
+ 'pxe get' requires two environment variables to be set:
+
+ pxefile_addr_r - should be set to a location in RAM large enough to hold
+ pxe files while they're being processed. Up to 16 config files may be
+ held in memory at once. The exact number and size of the files varies with
+ how the system is being used. A typical config file is a few hundred bytes
+ long.
+
+ bootfile,serverip - these two are typically set in the DHCP response
+ handler, and correspond to fields in the DHCP response.
+
+ 'pxe get' optionally supports these two environment variables being set:
+
+ ethaddr - this is the standard MAC address for the ethernet adapter in use.
+ 'pxe get' uses it to look for a configuration file specific to a system's
+ MAC address.
+
+ pxeuuid - this is a UUID in standard form using lower case hexadecimal
+ digits, for example, 550e8400-e29b-41d4-a716-446655440000. 'pxe get' uses
+ it to look for a configuration file based on the system's UUID.
+
+ File Paths
+ ----------
+ 'pxe get' repeatedly tries to download config files until it either
+ successfully downloads one or runs out of paths to try. The order and
+ contents of paths it tries mirrors exactly that of PXELINUX - you can
+ read in more detail about it at:
+
+ http://syslinux.zytor.com/wiki/index.php/Doc/pxelinux
+
+pxe boot
+--------
+ syntax: pxe boot [pxefile_addr_r]
+
+ Interprets a pxe file stored in memory.
+
+ pxefile_addr_r is an optional argument giving the location of the pxe file.
+ The file must be terminated with a NUL byte.
+
+ Environment
+ -----------
+ There are some environment variables that may need to be set, depending
+ on conditions.
+
+ pxefile_addr_r - if the optional argument pxefile_addr_r is not supplied,
+ an environment variable named pxefile_addr_r must be supplied. This is
+ typically the same value as is used for the 'pxe get' command.
+
+ bootfile - typically set in the DHCP response handler based on the
+ same field in the DHCP respone, this path is used to generate the base
+ directory that all other paths to files retrieved by 'pxe boot' will use.
+ If no bootfile is specified, paths used in pxe files will be used as is.
+
+ serverip - typically set in the DHCP response handler, this is the IP
+ address of the tftp server from which other files will be retrieved.
+
+ kernel_addr_r, initrd_addr_r - locations in RAM at which 'pxe boot' will
+ store the kernel and initrd it retrieves from tftp. These locations will
+ be passed to the bootm command to boot the kernel. These environment
+ variables are required to be set.
+
+ fdt_addr - the location of a fdt blob. If this is set, it will be passed
+ to bootm when booting a kernel.
+
+pxe file format
+===============
+The pxe file format is nearly a subset of the PXELINUX file format; see
+http://syslinux.zytor.com/wiki/index.php/PXELINUX. It's composed of one line
+commands - global commands, and commands specific to labels. Lines begining
+with # are treated as comments. White space between and at the beginning of
+lines is ignored.
+
+The size of pxe files and the number of labels is only limited by the amount
+of RAM available to U-boot. Memory for labels is dynamically allocated as
+they're parsed, and memory for pxe files is statically allocated, and its
+location is given by the pxefile_addr_r environment variable. The pxe code is
+not aware of the size of the pxefile memory and will outgrow it if pxe files
+are too large.
+
+Supported global commands
+-------------------------
+Unrecognized commands are ignored.
+
+default <label> - the label named here is treated as the default and is
+ the first label 'pxe boot' attempts to boot.
+
+menu title <string> - sets a title for the menu of labels being displayed.
+
+menu include <path> - use tftp to retrieve the pxe file at <path>, which
+ is then immediately parsed as if the start of its
+ contents were the next line in the current file. nesting
+ of include up to 16 files deep is supported.
+
+prompt <flag> - if 1, always prompt the user to enter a label to boot
+ from. if 0, only prompt the user if timeout expires.
+
+timeout <num> - wait for user input for <num>/10 seconds before
+ auto-booting a node.
+
+label <name> - begin a label definition. labels continue until
+ a command not recognized as a label command is seen,
+ or EOF is reached.
+
+Supported label commands
+------------------------
+labels end when a command not recognized as a label command is reached, or EOF.
+
+menu default - set this label as the default label to boot; this is
+ the same behavior as the global default command but
+ specified in a different way
+
+kernel <path> - if this label is chosen, use tftp to retrieve the kernel
+ at <path>. it will be stored at the address indicated in
+ the kernel_addr_r environment variable, and that address
+ will be passed to bootm to boot this kernel.
+
+append <string> - use <string> as the kernel command line when booting this
+ label.
+
+initrd <path> - if this label is chosen, use tftp to retrieve the initrd
+ at <path>. it will be stored at the address indicated in
+ the initrd_addr_r environment variable, and that address
+ will be passed to bootm.
+
+localboot <flag> - Run the command defined by "localcmd" in the environment.
+ <flag> is ignored and is only here to match the syntax of
+ PXELINUX config files.
+
+Example
+-------
+Here's a couple of example files to show how this works.
+
+------------/tftpboot/pxelinux.cfg/menus/linux.list----------
+menu title Linux selections
+
+# This is the default label
+label install
+ menu label Default Install Image
+ kernel kernels/install.bin
+ append console=ttyAMA0,38400 debug earlyprintk
+ initrd initrds/uzInitrdDebInstall
+
+# Just another label
+label linux-2.6.38
+ kernel kernels/linux-2.6.38.bin
+ append root=/dev/sdb1
+
+# The locally installed kernel
+label local
+ menu label Locally installed kernel
+ append root=/dev/sdb1
+ localboot 1
+-------------------------------------------------------------
+
+------------/tftpboot/pxelinux.cfg/default-------------------
+menu include pxelinux.cfg/menus/base.menu
+timeout 500
+
+default linux-2.6.38
+-------------------------------------------------------------
+
+When a pxe client retrieves and boots the default pxe file,
+'pxe boot' will wait for user input for 5 seconds before booting
+the linux-2.6.38 label, which will cause /tftpboot/kernels/linux-2.6.38.bin
+to be downloaded, and boot with the command line "root=/dev/sdb1"
+
+Differences with PXELINUX
+=========================
+The biggest difference between U-boot's pxe and PXELINUX is that since
+U-boot's pxe support is written entirely in C, it can run on any platform
+with network support in U-boot. Here are some other differences between
+PXELINUX and U-boot's pxe support.
+
+- U-boot's pxe does not support the PXELINUX DHCP option codes specified
+ in RFC 5071, but could be extended to do so.
+
+- when U-boot's pxe fails to boot, it will return control to U-boot,
+ allowing another command to run, other U-boot command, instead of resetting
+ the machine like PXELINUX.
+
+- U-boot's pxe doesn't rely on or provide an UNDI/PXE stack in memory, it
+ only uses U-boot.
+
+- U-boot's pxe doesn't provide the full menu implementation that PXELINUX
+ does, only a simple text based menu using the commands described in
+ this README. With PXELINUX, it's possible to have a graphical boot
+ menu, submenus, passwords, etc. U-boot's pxe could be extended to support
+ a more robust menuing system like that of PXELINUX's.
+
+- U-boot's pxe expects U-boot uimg's as kernels. Anything that would work
+ with the 'bootm' command in U-boot could work with the 'pxe boot' command.
+
+- U-boot's pxe doesn't recognize initrd options in the append command - you
+ must specify initrd files using the initrd command.
+
+- U-boot's pxe only recognizes a single file on the initrd command line. It
+ could be extended to support multiple.
+
+- in U-boot's pxe, the localboot command doesn't necessarily cause a local
+ disk boot - it will do whatever is defined in the 'localcmd' env
+ variable. And since it doesn't support a full UNDI/PXE stack, the
+ type field is ignored.
+
+- the interactive prompt in U-boot's pxe only allows you to choose a label
+ from the menu. If you want to boot something not listed, you can ctrl+c
+ out of 'pxe boot' and use existing U-boot commands to accomplish it.
diff --git a/include/common.h b/include/common.h
index ecf31ad78..b3c2e52ba 100644
--- a/include/common.h
+++ b/include/common.h
@@ -255,6 +255,9 @@ int print_buffer (ulong addr, void* data, uint width, uint count, uint linelen);
/* common/main.c */
void main_loop (void);
int run_command (const char *cmd, int flag);
+#ifdef CONFIG_CMD_PXE
+int run_command2(const char *cmd, int flag);
+#endif
int readline (const char *const prompt);
int readline_into_buffer (const char *const prompt, char * buffer);
int parse_line (char *, char *[]);
@@ -285,6 +288,9 @@ extern ulong load_addr; /* Default Load Address */
/* common/cmd_doc.c */
void doc_probe(unsigned long physadr);
+/* common/cmd_net.c */
+int do_tftpb(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[]);
+
/* common/cmd_nvedit.c */
int env_init (void);
void env_relocate (void);