unify common parts of extlinux and syslinux installer

Thus we can share same command line options and reduce a lot of dup
code...

Seems like a big patch, but the changes are quite safe, no much logical
change.

Signed-off-by: Alek Du <alek.du@intel.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>

9 files changed, 595 insertions, 11 deletions

diff --git a/libinstaller/Makefile b/libinstaller/Makefile
index ef3711dd..82c1990e 100644
--- a/libinstaller/Makefile
+++ b/libinstaller/Makefile
@@ -11,7 +11,7 @@ bootsect_bin.c: ../core/ldlinux.bss bin2c.pl
 	$(PERL) bin2c.pl syslinux_bootsect < $< > $@
 
 ldlinux_bin.c: ../core/ldlinux.sys bin2c.pl
-	$(PERL) bin2c.pl syslinux_ldlinux < $< > $@
+	$(PERL) bin2c.pl syslinux_ldlinux 512 < $< > $@
 
 extlinux_bss_bin.c: ../core/extlinux.bss bin2c.pl
 	$(PERL) bin2c.pl extlinux_bootsect < $< > $@
diff --git a/libinstaller/setadv.c b/libinstaller/setadv.c
index d18ac927..682b883e 100644
--- a/libinstaller/setadv.c
+++ b/libinstaller/setadv.c
@@ -19,10 +19,22 @@
  * Return 0 on success, -1 on error, and set errno.
  *
  */
+#define  _GNU_SOURCE
 
+#include <stdio.h>
+#include <stdlib.h>
+#include <stddef.h>
+#include <stdint.h>
 #include <string.h>
+#include <getopt.h>
+#include <unistd.h>
 #include <errno.h>
+#include <fcntl.h>
+#include <sys/ioctl.h>
+#include <sys/stat.h>
+#include <sys/types.h>
 #include "syslxint.h"
+#include "syslxcom.h"
 
 unsigned char syslinux_adv[2 * ADV_SIZE];
 
@@ -158,3 +170,127 @@ int syslinux_validate_adv(unsigned char *advbuf)
 	return -1;
     }
 }
+
+/*
+ * Read the ADV from an existing instance, or initialize if invalid.
+ * Returns -1 on fatal errors, 0 if ADV is okay, and 1 if no valid
+ * ADV was found.
+ */
+int read_adv(const char *path, const char *cfg)
+{
+    char *file;
+    int fd = -1;
+    struct stat st;
+    int err = 0;
+
+    err = asprintf(&file, "%s%s%s",
+	path, path[0] && path[strlen(path) - 1] == '/' ? "" : "/", cfg);
+
+    if (!file) {
+	perror(program);
+	return -1;
+    }
+
+    fd = open(file, O_RDONLY);
+    if (fd < 0) {
+	if (errno != ENOENT) {
+	    err = -1;
+	} else {
+	    syslinux_reset_adv(syslinux_adv);
+	}
+    } else if (fstat(fd, &st)) {
+	err = -1;
+    } else if (st.st_size < 2 * ADV_SIZE) {
+	/* Too small to be useful */
+	syslinux_reset_adv(syslinux_adv);
+	err = 0;		/* Nothing to read... */
+    } else if (xpread(fd, syslinux_adv, 2 * ADV_SIZE,
+		      st.st_size - 2 * ADV_SIZE) != 2 * ADV_SIZE) {
+	err = -1;
+    } else {
+	/* We got it... maybe? */
+	err = syslinux_validate_adv(syslinux_adv) ? 1 : 0;
+    }
+
+    if (err < 0)
+	perror(file);
+
+    if (fd >= 0)
+	close(fd);
+    if (file)
+	free(file);
+
+    return err;
+}
+
+/*
+ * Update the ADV in an existing installation.
+ */
+int write_adv(const char *path, const char *cfg)
+{
+    unsigned char advtmp[2 * ADV_SIZE];
+    char *file;
+    int fd = -1;
+    struct stat st, xst;
+    int err = 0;
+
+    err = asprintf(&file, "%s%s%s",
+	path, path[0] && path[strlen(path) - 1] == '/' ? "" : "/", cfg);
+
+    if (!file) {
+	perror(program);
+	return -1;
+    }
+
+    fd = open(file, O_RDONLY);
+    if (fd < 0) {
+	err = -1;
+    } else if (fstat(fd, &st)) {
+	err = -1;
+    } else if (st.st_size < 2 * ADV_SIZE) {
+	/* Too small to be useful */
+	err = -2;
+    } else if (xpread(fd, advtmp, 2 * ADV_SIZE,
+		      st.st_size - 2 * ADV_SIZE) != 2 * ADV_SIZE) {
+	err = -1;
+    } else {
+	/* We got it... maybe? */
+	err = syslinux_validate_adv(advtmp) ? -2 : 0;
+	if (!err) {
+	    /* Got a good one, write our own ADV here */
+	    clear_attributes(fd);
+
+	    /* Need to re-open read-write */
+	    close(fd);
+	    fd = open(file, O_RDWR | O_SYNC);
+	    if (fd < 0) {
+		err = -1;
+	    } else if (fstat(fd, &xst) || xst.st_ino != st.st_ino ||
+		       xst.st_dev != st.st_dev || xst.st_size != st.st_size) {
+		fprintf(stderr, "%s: race condition on write\n", file);
+		err = -2;
+	    }
+	    /* Write our own version ... */
+	    if (xpwrite(fd, syslinux_adv, 2 * ADV_SIZE,
+			st.st_size - 2 * ADV_SIZE) != 2 * ADV_SIZE) {
+		err = -1;
+	    }
+
+	    sync();
+	    set_attributes(fd);
+	}
+    }
+
+    if (err == -2)
+	fprintf(stderr, "%s: cannot write auxilliary data (need --update)?\n",
+		file);
+    else if (err == -1)
+	perror(file);
+
+    if (fd >= 0)
+	close(fd);
+    if (file)
+	free(file);
+
+    return err;
+}
diff --git a/libinstaller/setadv.h b/libinstaller/setadv.h
new file mode 100644
index 00000000..32bdfec1
--- /dev/null
+++ b/libinstaller/setadv.h
@@ -0,0 +1,16 @@
+#ifndef _H_SET_ADV_
+#define _H_SET_ADV_
+
+/* ADV information */
+#define ADV_SIZE	512	/* Total size */
+#define ADV_LEN		(ADV_SIZE-3*4)	/* Usable data size */
+
+extern unsigned char syslinux_adv[2 * ADV_SIZE];
+
+int syslinux_setadv(int tag, size_t size, const void *data);
+void syslinux_reset_adv(unsigned char *advbuf);
+int syslinux_validate_adv(unsigned char *advbuf);
+int read_adv(const char *path, const char *cfg);
+int write_adv(const char *path, const char *cfg);
+
+#endif
diff --git a/libinstaller/syslinux.h b/libinstaller/syslinux.h
index 8ed1edbe..8d0212c8 100644
--- a/libinstaller/syslinux.h
+++ b/libinstaller/syslinux.h
@@ -15,6 +15,7 @@
 
 #include <inttypes.h>
 #include "advconst.h"
+#include "setadv.h"
 
 /* The standard boot sector and ldlinux image */
 extern unsigned char syslinux_bootsect[];
@@ -43,13 +44,4 @@ const char *syslinux_check_bootsect(const void *bs);
 int syslinux_patch(const uint32_t * sectors, int nsectors,
 		   int stupid, int raid_mode);
 
-/* ADV information */
-#define ADV_SIZE	512	/* Total size */
-#define ADV_LEN		(ADV_SIZE-3*4)	/* Usable data size */
-extern unsigned char syslinux_adv[2 * ADV_SIZE];
-
-int syslinux_setadv(int tag, size_t size, const void *data);
-void syslinux_reset_adv(unsigned char *advbuf);
-int syslinux_validate_adv(unsigned char *advbuf);
-
 #endif
diff --git a/libinstaller/syslxcom.c b/libinstaller/syslxcom.c
new file mode 100644
index 00000000..825419b4
--- /dev/null
+++ b/libinstaller/syslxcom.c
@@ -0,0 +1,218 @@
+/* ----------------------------------------------------------------------- *
+ *
+ *   Copyright 2010 Intel Corp. - All Rights Reserved
+ *
+ *   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, Inc., 53 Temple Place Ste 330,
+ *   Boston MA 02111-1307, USA; either version 2 of the License, or
+ *   (at your option) any later version; incorporated herein by reference.
+ *
+ * ----------------------------------------------------------------------- */
+
+/*
+ * syslxcom.c
+ *
+ * common functions for extlinux & syslinux installer
+ *
+ */
+#define  _GNU_SOURCE
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <stddef.h>
+#include <stdint.h>
+#include <string.h>
+#include <getopt.h>
+#include <unistd.h>
+#include <errno.h>
+#include <sys/ioctl.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <sys/mount.h>
+#include <sys/vfs.h>
+#include <linux/fs.h>		/* FIGETBSZ, FIBMAP */
+#include <linux/msdos_fs.h>	/* FAT_IOCTL_SET_ATTRIBUTES */
+#include "syslxcom.h"
+
+const char *program;
+
+int fs_type;
+
+#ifdef DEBUG
+# define dprintf printf
+#else
+# define dprintf(...) ((void)0)
+#endif
+
+#define SECTOR_SHIFT	9
+#define EXT2_IMMUTABLE_FL		0x00000010	/* Immutable file */
+
+/*
+ * ioctl commands
+ */
+#define	EXT2_IOC_GETFLAGS		_IOR('f', 1, long)
+#define	EXT2_IOC_SETFLAGS		_IOW('f', 2, long)
+#define	EXT2_IOC_GETVERSION		_IOR('v', 1, long)
+#define	EXT2_IOC_SETVERSION		_IOW('v', 2, long)
+
+static void die(const char *msg)
+{
+    fputs(msg, stderr);
+    exit(1);
+}
+
+/*
+ * read/write wrapper functions
+ */
+ssize_t xpread(int fd, void *buf, size_t count, off_t offset)
+{
+    char *bufp = (char *)buf;
+    ssize_t rv;
+    ssize_t done = 0;
+
+    while (count) {
+	rv = pread(fd, bufp, count, offset);
+	if (rv == 0) {
+	    die("short read");
+	} else if (rv == -1) {
+	    if (errno == EINTR) {
+		continue;
+	    } else {
+		die(strerror(errno));
+	    }
+	} else {
+	    bufp += rv;
+	    offset += rv;
+	    done += rv;
+	    count -= rv;
+	}
+    }
+
+    return done;
+}
+
+ssize_t xpwrite(int fd, const void *buf, size_t count, off_t offset)
+{
+    const char *bufp = (const char *)buf;
+    ssize_t rv;
+    ssize_t done = 0;
+
+    while (count) {
+	rv = pwrite(fd, bufp, count, offset);
+	if (rv == 0) {
+	    die("short write");
+	} else if (rv == -1) {
+	    if (errno == EINTR) {
+		continue;
+	    } else {
+		die(strerror(errno));
+	    }
+	} else {
+	    bufp += rv;
+	    offset += rv;
+	    done += rv;
+	    count -= rv;
+	}
+    }
+
+    return done;
+}
+
+/*
+ * Set and clear file attributes
+ */
+void clear_attributes(int fd)
+{
+    struct stat st;
+
+    if (!fstat(fd, &st)) {
+	switch (fs_type) {
+	case EXT2:
+	{
+	    int flags;
+
+	    if (!ioctl(fd, EXT2_IOC_GETFLAGS, &flags)) {
+		flags &= ~EXT2_IMMUTABLE_FL;
+		ioctl(fd, EXT2_IOC_SETFLAGS, &flags);
+	    }
+	    break;
+	}
+	case VFAT:
+	{
+	    uint32_t attr = 0x00; /* Clear all attributes */
+	    ioctl(fd, FAT_IOCTL_SET_ATTRIBUTES, &attr);
+	    break;
+	}
+	default:
+	    break;
+	}
+	fchmod(fd, st.st_mode | S_IWUSR);
+    }
+}
+
+void set_attributes(int fd)
+{
+    struct stat st;
+
+    if (!fstat(fd, &st)) {
+	fchmod(fd, st.st_mode & (S_IRUSR | S_IRGRP | S_IROTH));
+	switch (fs_type) {
+	case EXT2:
+	{
+	    int flags;
+
+	    if (st.st_uid == 0 && !ioctl(fd, EXT2_IOC_GETFLAGS, &flags)) {
+		flags |= EXT2_IMMUTABLE_FL;
+		ioctl(fd, EXT2_IOC_SETFLAGS, &flags);
+	    }
+	    break;
+	}
+	case VFAT:
+	{
+	    uint32_t attr = 0x07; /* Hidden+System+Readonly */
+	    ioctl(fd, FAT_IOCTL_SET_ATTRIBUTES, &attr);
+	    break;
+	}
+	default:
+	    break;
+	}
+    }
+}
+
+/*
+ * Produce file map
+ */
+int sectmap(int fd, uint32_t * sectors, int nsectors)
+{
+    unsigned int blksize, blk, nblk;
+    unsigned int i;
+
+    /* Get block size */
+    if (ioctl(fd, FIGETBSZ, &blksize))
+	return -1;
+
+    /* Number of sectors per block */
+    blksize >>= SECTOR_SHIFT;
+
+    nblk = 0;
+    while (nsectors) {
+
+	blk = nblk++;
+	dprintf("querying block %u\n", blk);
+	if (ioctl(fd, FIBMAP, &blk))
+	    return -1;
+
+	blk *= blksize;
+	for (i = 0; i < blksize; i++) {
+	    if (!nsectors)
+		return 0;
+
+	    dprintf("Sector: %10u\n", blk);
+	    *sectors++ = blk++;
+	    nsectors--;
+	}
+    }
+
+    return 0;
+}
diff --git a/libinstaller/syslxcom.h b/libinstaller/syslxcom.h
new file mode 100644
index 00000000..ba4f1d00
--- /dev/null
+++ b/libinstaller/syslxcom.h
@@ -0,0 +1,20 @@
+#ifndef _H_SYSLXCOM_
+#define _H_SYSLXCOM_
+
+/* Global fs_type for handling fat, ext2/3/4 and btrfs */
+enum filesystem {
+    NONE,
+    EXT2,
+    BTRFS,
+    VFAT,
+};
+
+extern int fs_type;
+extern const char *program;
+ssize_t xpread(int fd, void *buf, size_t count, off_t offset);
+ssize_t xpwrite(int fd, const void *buf, size_t count, off_t offset);
+void clear_attributes(int fd);
+void set_attributes(int fd);
+int sectmap(int fd, uint32_t * sectors, int nsectors);
+
+#endif
diff --git a/libinstaller/syslxmod.c b/libinstaller/syslxmod.c
index be06b9a2..9ab139c6 100644
--- a/libinstaller/syslxmod.c
+++ b/libinstaller/syslxmod.c
@@ -261,7 +261,7 @@ int syslinux_patch(const uint32_t * sectors, int nsectors,
     /* Set up the totals */
     dw = syslinux_ldlinux_len >> 2;	/* COMPLETE dwords, excluding ADV */
     set_16_sl(&patcharea->data_sectors, nsect);	/* Not including ADVs */
-    set_16_sl(&patcharea->adv_sectors, 0);	/* ADVs not supported yet */
+    set_16_sl(&patcharea->adv_sectors, 2);	/* ADVs need 2 sectors */
     set_32_sl(&patcharea->dwords, dw);
 
     /* Set the sector pointers */
@@ -269,6 +269,7 @@ int syslinux_patch(const uint32_t * sectors, int nsectors,
 		       get_16_sl(&patcharea->secptroffset));
     nptrs = get_16_sl(&patcharea->secptrcnt);
 
+    nsect += 2;
     while (--nsect) { /* the first sector is in bs->NextSector */
 	set_32_sl(wp++, *sectors++);
 	nptrs--;
diff --git a/libinstaller/syslxopt.c b/libinstaller/syslxopt.c
new file mode 100644
index 00000000..7718de3a
--- /dev/null
+++ b/libinstaller/syslxopt.c
@@ -0,0 +1,171 @@
+/* ----------------------------------------------------------------------- *
+ *
+ *   Copyright 2010 Intel Corp. - All Rights Reserved
+ *
+ *   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, Inc., 53 Temple Place Ste 330,
+ *   Boston MA 02111-1307, USA; either version 2 of the License, or
+ *   (at your option) any later version; incorporated herein by reference.
+ *
+ * ----------------------------------------------------------------------- */
+
+/*
+ * syslxopt.c
+ *
+ * parse cmdline for extlinux and syslinux installer
+ *
+ */
+#include <stdio.h>
+#include <stdlib.h>
+#include <stddef.h>
+#include <stdint.h>
+#include <getopt.h>
+#include <sysexits.h>
+#include "../version.h"
+#include "syslxcom.h"
+#include "syslxopt.h"
+
+/* These are the options we can set their values */
+struct sys_options opt = {
+    .sectors = 0,
+    .heads = 0,
+    .raid_mode = 0,
+    .stupid_mode = 0,
+    .reset_adv = 0,
+    .set_once = NULL,
+    .update_only = -1,
+    .directory = NULL,
+    .device = NULL,
+    .offset = 0,
+};
+
+const struct option long_options[] = {
+    {"install", 0, NULL, 'i'},
+    {"directory", 1, NULL, 'd'},
+    {"offset", 1, NULL, 'f'},
+    {"update", 0, NULL, 'U'},
+    {"zipdrive", 0, NULL, 'z'},
+    {"sectors", 1, NULL, 'S'},
+    {"stupid", 0, NULL, 's'},
+    {"heads", 1, NULL, 'H'},
+    {"raid-mode", 0, NULL, 'r'},
+    {"version", 0, NULL, 'v'},
+    {"help", 0, NULL, 'h'},
+    {"once", 1, NULL, 'o'},
+    {"clear-once", 0, NULL, 'O'},
+    {"reset-adv", 0, NULL, OPT_RESET_ADV},
+    {0, 0, 0, 0}
+};
+
+const char short_options[] = "id:f:UuzS:H:rvho:O";
+
+void __attribute__ ((noreturn)) usage(int rv, int mode)
+{
+    if (mode) /* for unmounted fs installation */
+	fprintf(stderr,
+	    "Usage: %s [options] device\n"
+	    "  --offset     -f Offset of the file system on the device \n"
+	    "  --directory  -d  Directory for installation target\n",
+	    program);
+    else /* actually extlinux can also use -d to provide directory too */
+	fprintf(stderr,
+	    "Usage: %s [options] directory\n",
+	    program);
+    fprintf(stderr,
+	    "  --install    -i  Install over the current bootsector\n"
+	    "  --update     -U  Update a previous EXTLINUX installation\n"
+	    "  --zip        -z  Force zipdrive geometry (-H 64 -S 32)\n"
+	    "  --sectors=#  -S  Force the number of sectors per track\n"
+	    "  --heads=#    -H  Force number of heads\n"
+	    "  --stupid     -s  Slow, safe and stupid mode\n"
+	    "  --raid       -r  Fall back to the next device on boot failure\n"
+	    "  --once=...   -o  Execute a command once upon boot\n"
+	    "  --clear-once -O  Clear the boot-once command\n"
+	    "  --reset-adv      Reset auxilliary data\n"
+	    "\n"
+	    "  Note: geometry is determined at boot time for devices which\n"
+	    "  are considered hard disks by the BIOS.  Unfortunately, this is\n"
+	    "  not possible for devices which are considered floppy disks,\n"
+	    "  which includes zipdisks and LS-120 superfloppies.\n"
+	    "\n"
+	    "  The -z option is useful for USB devices which are considered\n"
+	    "  hard disks by some BIOSes and zipdrives by other BIOSes.\n"
+	    );
+
+    exit(rv);
+}
+
+void parse_options(int argc, char *argv[], int mode)
+{
+    int o;
+
+    program = argv[0];
+    while ((o = getopt_long(argc, argv, short_options,
+			    long_options, NULL)) != EOF) {
+	switch (o) {
+	case 'z':
+	    opt.heads = 64;
+	    opt.sectors = 32;
+	    break;
+	case 'S':
+	    opt.sectors = strtoul(optarg, NULL, 0);
+	    if (opt.sectors < 1 || opt.sectors > 63) {
+		fprintf(stderr,
+			"%s: invalid number of sectors: %u (must be 1-63)\n",
+			program, opt.sectors);
+		exit(EX_USAGE);
+	    }
+	    break;
+	case 'H':
+	    opt.heads = strtoul(optarg, NULL, 0);
+	    if (opt.heads < 1 || opt.heads > 256) {
+		fprintf(stderr,
+			"%s: invalid number of heads: %u (must be 1-256)\n",
+			program, opt.heads);
+		exit(EX_USAGE);
+	    }
+	    break;
+	case 'r':
+	    opt.raid_mode = 1;
+	    break;
+	case 's':
+	    opt.stupid_mode = 1;
+	    break;
+	case 'i':
+	    opt.update_only = 0;
+	    break;
+	case 'u':
+	case 'U':
+	    opt.update_only = 1;
+	    break;
+	case 'h':
+	    usage(0, mode);
+	    break;
+	case 'o':
+	    opt.set_once = optarg;
+	    break;
+	case 'f':
+	    opt.offset = strtoul(optarg, NULL, 0);
+	case 'O':
+	    opt.set_once = "";
+	    break;
+	case 'd':
+	    opt.directory = optarg;
+	case OPT_RESET_ADV:
+	    opt.reset_adv = 1;
+	    break;
+	case 'v':
+	    fputs(program, stderr);
+	    fputs(" " VERSION_STR
+		  "  Copyright 1994-" YEAR_STR " H. Peter Anvin \n", stderr);
+	    exit(0);
+	default:
+	    usage(EX_USAGE, mode);
+	}
+    }
+    if (mode)
+	opt.device = argv[optind];
+    else if (!opt.directory)
+	opt.directory = argv[optind];
+}
diff --git a/libinstaller/syslxopt.h b/libinstaller/syslxopt.h
new file mode 100644
index 00000000..d925fa34
--- /dev/null
+++ b/libinstaller/syslxopt.h
@@ -0,0 +1,30 @@
+#ifndef _H_SYSLXOPT_
+#define _H_SYSLXOPT_
+
+/* These are the options we can set and their values */
+struct sys_options {
+    unsigned int sectors;
+    unsigned int heads;
+    int raid_mode;
+    int stupid_mode;
+    int reset_adv;
+    const char *set_once;
+    int update_only;
+    const char *directory;
+    const char *device;
+    unsigned int offset;
+};
+
+enum long_only_opt {
+    OPT_NONE,
+    OPT_RESET_ADV,
+};
+
+void __attribute__ ((noreturn)) usage(int rv, int mode);
+void parse_options(int argc, char *argv[], int mode);
+
+extern struct sys_options opt;
+extern const struct option long_options[];
+extern const char short_options[];
+
+#endif