From 24fa50961451b7b21081e4d16836952b17eb5fb3 Mon Sep 17 00:00:00 2001 From: Luciano Rocha Date: Sat, 10 Feb 2007 01:44:45 -0800 Subject: [PATCH] [PATCH] usr/gen_init_cpio.c: support for hard links Extend usr/gen_init_cpio.c "file" entry, adding support for hard links. Previous format: file New format: file [] The hard links specification is optional, keeping the previous behaviour. All hard links are defined sequentially in the resulting cpio and the file data is present only in the last link. This is the behaviour of GNU's cpio and is supported by the kernel initramfs extractor. Signed-off-by: Luciano Rocha Cc: Al Viro Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- usr/gen_init_cpio.c | 122 +++++++++++++++++++++++++++++++------------- 1 file changed, 86 insertions(+), 36 deletions(-) diff --git a/usr/gen_init_cpio.c b/usr/gen_init_cpio.c index 83acd6cc0b3cd7..8365db6cfe0644 100644 --- a/usr/gen_init_cpio.c +++ b/usr/gen_init_cpio.c @@ -14,6 +14,7 @@ * Original work by Jeff Garzik * * External file lists, symlink, pipe and fifo support by Thayne Harbaugh + * Hard link support by Luciano Rocha */ #define xstr(s) #s @@ -286,16 +287,19 @@ static int cpio_mknod_line(const char *line) return rc; } -/* Not marked static to keep the compiler quiet, as no one uses this yet... */ static int cpio_mkfile(const char *name, const char *location, - unsigned int mode, uid_t uid, gid_t gid) + unsigned int mode, uid_t uid, gid_t gid, + unsigned int nlinks) { char s[256]; char *filebuf = NULL; struct stat buf; + long size; int file = -1; int retval; int rc = -1; + int namesize; + int i; mode |= S_IFREG; @@ -323,29 +327,41 @@ static int cpio_mkfile(const char *name, const char *location, goto error; } - sprintf(s,"%s%08X%08X%08lX%08lX%08X%08lX" - "%08X%08X%08X%08X%08X%08X%08X", - "070701", /* magic */ - ino++, /* ino */ - mode, /* mode */ - (long) uid, /* uid */ - (long) gid, /* gid */ - 1, /* nlink */ - (long) buf.st_mtime, /* mtime */ - (int) buf.st_size, /* filesize */ - 3, /* major */ - 1, /* minor */ - 0, /* rmajor */ - 0, /* rminor */ - (unsigned)strlen(name) + 1,/* namesize */ - 0); /* chksum */ - push_hdr(s); - push_string(name); - push_pad(); + size = 0; + for (i = 1; i <= nlinks; i++) { + /* data goes on last link */ + if (i == nlinks) size = buf.st_size; + + namesize = strlen(name) + 1; + sprintf(s,"%s%08X%08X%08lX%08lX%08X%08lX" + "%08lX%08X%08X%08X%08X%08X%08X", + "070701", /* magic */ + ino, /* ino */ + mode, /* mode */ + (long) uid, /* uid */ + (long) gid, /* gid */ + nlinks, /* nlink */ + (long) buf.st_mtime, /* mtime */ + size, /* filesize */ + 3, /* major */ + 1, /* minor */ + 0, /* rmajor */ + 0, /* rminor */ + namesize, /* namesize */ + 0); /* chksum */ + push_hdr(s); + push_string(name); + push_pad(); + + if (size) { + fwrite(filebuf, size, 1, stdout); + offset += size; + push_pad(); + } - fwrite(filebuf, buf.st_size, 1, stdout); - offset += buf.st_size; - push_pad(); + name += namesize; + } + ino++; rc = 0; error: @@ -357,18 +373,51 @@ static int cpio_mkfile(const char *name, const char *location, static int cpio_mkfile_line(const char *line) { char name[PATH_MAX + 1]; + char *dname = NULL; /* malloc'ed buffer for hard links */ char location[PATH_MAX + 1]; unsigned int mode; int uid; int gid; + int nlinks = 1; + int end = 0, dname_len = 0; int rc = -1; - if (5 != sscanf(line, "%" str(PATH_MAX) "s %" str(PATH_MAX) "s %o %d %d", name, location, &mode, &uid, &gid)) { + if (5 > sscanf(line, "%" str(PATH_MAX) "s %" str(PATH_MAX) + "s %o %d %d %n", + name, location, &mode, &uid, &gid, &end)) { fprintf(stderr, "Unrecognized file format '%s'", line); goto fail; } - rc = cpio_mkfile(name, location, mode, uid, gid); + if (end && isgraph(line[end])) { + int len; + int nend; + + dname = malloc(strlen(line)); + if (!dname) { + fprintf (stderr, "out of memory (%d)\n", dname_len); + goto fail; + } + + dname_len = strlen(name) + 1; + memcpy(dname, name, dname_len); + + do { + nend = 0; + if (sscanf(line + end, "%" str(PATH_MAX) "s %n", + name, &nend) < 1) + break; + len = strlen(name) + 1; + memcpy(dname + dname_len, name, len); + dname_len += len; + nlinks++; + end += nend; + } while (isgraph(line[end])); + } else { + dname = name; + } + rc = cpio_mkfile(dname, location, mode, uid, gid, nlinks); fail: + if (dname_len) free(dname); return rc; } @@ -381,22 +430,23 @@ void usage(const char *prog) "describe the files to be included in the initramfs archive:\n" "\n" "# a comment\n" - "file \n" + "file []\n" "dir \n" "nod \n" "slink \n" "pipe \n" "sock \n" "\n" - " name of the file/dir/nod/etc in the archive\n" - " location of the file in the current filesystem\n" - " link target\n" - " mode/permissions of the file\n" - " user id (0=root)\n" - " group id (0=root)\n" - " device type (b=block, c=character)\n" - " major number of nod\n" - " minor number of nod\n" + " name of the file/dir/nod/etc in the archive\n" + " location of the file in the current filesystem\n" + " link target\n" + " mode/permissions of the file\n" + " user id (0=root)\n" + " group id (0=root)\n" + " device type (b=block, c=character)\n" + " major number of nod\n" + " minor number of nod\n" + " space separated list of other links to file\n" "\n" "example:\n" "# A simple initramfs\n"