X-Git-Url: http://git.annexia.org/?a=blobdiff_plain;f=helper%2Fmain.c;h=b769bc795d38a73848438c6f47250be5ec345efb;hb=6d9051df32b90c6a4fe6ca1ff9e771b7dfe004fa;hp=a81cf61686ea43bd0474825e3633d63a30acd537;hpb=c0a9555e8559a0dbf432367f87c59c2a49520c99;p=febootstrap.git diff --git a/helper/main.c b/helper/main.c index a81cf61..b769bc7 100644 --- a/helper/main.c +++ b/helper/main.c @@ -16,80 +16,53 @@ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */ -/* This script builds the supermin appliance on the fly each - * time the appliance runs. - * - * *NOTE*: This program is designed to be very short-lived, and so we - * don't normally bother to free up any memory that we allocate. - * That's not completely true - we free up stuff if it's obvious and - * easy to free up, and ignore the rest. - */ - #include #include #include -#include -#include #include #include -#include -#include #include #include #include -#include -#include #include #include -#include #include +#include +#include #include "error.h" -#include "filevercmp.h" -#include "fts_.h" -#include "full-write.h" -#include "hash.h" -#include "hash-pjw.h" -#include "xalloc.h" -#include "xvasprintf.h" +#include "xstrtol.h" -/* Directory containing candidate kernels. We could make this - * configurable at some point. - */ -#define KERNELDIR "/boot" -#define MODULESDIR "/lib/modules" - -/* Buffer size used in copy operations throughout. Large for - * greatest efficiency. - */ -#define BUFFER_SIZE 65536 +#include "helper.h" -static struct timeval start_t; -static int verbose = 0; - -static void print_timestamped_message (const char *fs, ...); -static const char *create_kernel (const char *hostcpu, const char *kernel); -static void create_appliance (char **inputs, int nr_inputs, const char *whitelist, const char *modpath, const char *initrd); +struct timeval start_t; +int verbose = 0; enum { HELP_OPTION = CHAR_MAX + 1 }; -static const char *options = "k:vV"; +static const char *options = "f:g:k:u:vV"; static const struct option long_options[] = { { "help", 0, 0, HELP_OPTION }, + { "format", required_argument, 0, 'f' }, + { "group", 0, 0, 'g' }, { "kmods", required_argument, 0, 'k' }, + { "user", 0, 0, 'u' }, { "verbose", 0, 0, 'v' }, { "version", 0, 0, 'V' }, { 0, 0, 0, 0 } }; static void -usage (const char *progname) +usage (FILE *f, const char *progname) { - printf ("%s: build the supermin appliance on the fly\n" + fprintf (f, + "%s: build the supermin appliance on the fly\n" "\n" "Usage:\n" - " %s [-options] inputs [...] whitelist host_cpu kernel initrd\n" + " %s [-options] inputs [...] host_cpu kernel initrd\n" + " %s -f ext2 inputs [...] host_cpu kernel initrd appliance\n" + " %s -f checksum inputs [...] host_cpu\n" " %s --help\n" " %s --version\n" "\n" @@ -104,13 +77,79 @@ usage (const char *progname) "Options:\n" " --help\n" " Display this help text and exit.\n" + " -f cpio|ext2|checksum | --format cpio|ext2|checksum\n" + " Specify output format (default: cpio).\n" + " -u user\n" + " The user name or uid the appliance will run as. Use of this\n" + " option requires root privileges.\n" + " -g group\n" + " The group name or gid the appliance will run as. Use of\n" + " this option requires root privileges.\n" " -k file | --kmods file\n" " Specify kernel module whitelist.\n" " --verbose | -v\n" " Enable verbose messages (give multiple times for more verbosity).\n" " --version | -V\n" " Display version number and exit.\n", - progname, progname, progname, progname); + progname, progname, progname, progname, progname, progname); +} + +static uid_t +parseuser (const char *id, const char *progname) +{ + + struct passwd *pwd; + + errno = 0; + pwd = getpwnam (id); + + if (NULL == pwd) { + if (errno != 0) { + fprintf (stderr, "Error looking up user: %m\n"); + exit (EXIT_FAILURE); + } + + long val; + int err = xstrtol (id, NULL, 10, &val, ""); + if (err != LONGINT_OK) { + fprintf (stderr, "%s is not a valid user name or uid\n", id); + usage (stderr, progname); + exit (EXIT_FAILURE); + } + + return (uid_t) val; + } + + return pwd->pw_uid; +} + +static gid_t +parsegroup (const char *id, const char *progname) +{ + + struct group *grp; + + errno = 0; + grp = getgrnam (id); + + if (NULL == grp) { + if (errno != 0) { + fprintf (stderr, "Error looking up group: %m\n"); + exit (EXIT_FAILURE); + } + + long val; + int err = xstrtol (id, NULL, 10, &val, ""); + if (err != LONGINT_OK) { + fprintf (stderr, "%s is not a valid group name or gid\n", id); + usage (stderr, progname); + exit (EXIT_FAILURE); + } + + return (gid_t) val; + } + + return grp->gr_gid; } int @@ -119,8 +158,12 @@ main (int argc, char *argv[]) /* First thing: start the clock. */ gettimeofday (&start_t, NULL); + const char *format = "cpio"; const char *whitelist = NULL; + uid_t euid = geteuid (); + gid_t egid = getegid (); + /* Command line arguments. */ for (;;) { int c = getopt_long (argc, argv, options, long_options, NULL); @@ -128,9 +171,21 @@ main (int argc, char *argv[]) switch (c) { case HELP_OPTION: - usage (argv[0]); + usage (stdout, argv[0]); exit (EXIT_SUCCESS); + case 'f': + format = optarg; + break; + + case 'u': + euid = parseuser (optarg, argv[0]); + break; + + case 'g': + egid = parsegroup (optarg, argv[0]); + break; + case 'k': whitelist = optarg; break; @@ -144,893 +199,125 @@ main (int argc, char *argv[]) exit (EXIT_SUCCESS); default: - usage (argv[0]); + usage (stderr, argv[0]); + exit (EXIT_FAILURE); + } + } + + /* We need to set the real, not effective, uid here to work round a + * misfeature in bash. bash will automatically reset euid to uid when + * invoked. As shell is used in places by febootstrap-supermin-helper, this + * results in code running with varying privilege. */ + uid_t uid = getuid (); + gid_t gid = getgid (); + + if (uid != euid || gid != egid) { + if (uid != 0) { + fprintf (stderr, "The -u and -g options require root privileges.\n"); + usage (stderr, argv[0]); + exit (EXIT_FAILURE); + } + + /* Need to become root first because setgid and setuid require it */ + if (seteuid (0) == -1) { + perror ("seteuid"); + exit (EXIT_FAILURE); + } + + /* Set gid and uid to command-line parameters */ + if (setgid (egid) == -1) { + perror ("setgid"); + exit (EXIT_FAILURE); + } + if (setuid (euid) == -1) { + perror ("setuid"); exit (EXIT_FAILURE); } } + /* Select the correct writer module. */ + struct writer *writer; + int nr_outputs; + + if (strcmp (format, "cpio") == 0) { + writer = &cpio_writer; + nr_outputs = 2; /* kernel and appliance (== initrd) */ + } + else if (strcmp (format, "ext2") == 0) { + writer = &ext2_writer; + nr_outputs = 3; /* kernel, initrd, appliance */ + } + else if (strcmp (format, "checksum") == 0) { + writer = &checksum_writer; + nr_outputs = 0; /* (none) */ + } + else { + fprintf (stderr, + "%s: incorrect output format (-f): must be cpio|ext2|checksum\n", + argv[0]); + exit (EXIT_FAILURE); + } + + /* [optind .. optind+nr_inputs-1] hostcpu [argc-nr_outputs-1 .. argc-1] + * <---- nr_inputs ----> 1 <---- nr_outputs ----> + */ char **inputs = &argv[optind]; - int nr_inputs = argc - optind - 3; + int nr_inputs = argc - nr_outputs - 1 - optind; + char **outputs = &argv[optind+nr_inputs+1]; + /*assert (outputs [nr_outputs] == NULL); + assert (inputs [nr_inputs + 1 + nr_outputs] == NULL);*/ if (nr_inputs < 1) { - usage (argv[0]); + fprintf (stderr, "%s: not enough files specified on the command line\n", + argv[0]); exit (EXIT_FAILURE); } /* See: https://bugzilla.redhat.com/show_bug.cgi?id=558593 */ - const char *hostcpu = argv[argc-3]; + const char *hostcpu = outputs[-1]; /* Output files. */ - const char *kernel = argv[argc-2]; - const char *initrd = argv[argc-1]; + const char *kernel = NULL, *initrd = NULL, *appliance = NULL; + if (nr_outputs > 0) + kernel = outputs[0]; + if (nr_outputs > 1) + initrd = appliance = outputs[1]; + if (nr_outputs > 2) + appliance = outputs[2]; if (verbose) { print_timestamped_message ("whitelist = %s, " "host_cpu = %s, " "kernel = %s, " - "initrd = %s", + "initrd = %s, " + "appliance = %s", whitelist ? : "(not specified)", - hostcpu, kernel, initrd); + hostcpu, kernel, initrd, appliance); int i; for (i = 0; i < nr_inputs; ++i) print_timestamped_message ("inputs[%d] = %s", i, inputs[i]); } /* Remove the output files if they exist. */ - unlink (kernel); - unlink (initrd); + if (kernel) + unlink (kernel); + if (initrd) + unlink (initrd); + if (appliance && initrd != appliance) + unlink (appliance); /* Create kernel output file. */ - const char *modpath; - modpath = create_kernel (hostcpu, kernel); + const char *modpath = create_kernel (hostcpu, kernel); if (verbose) print_timestamped_message ("finished creating kernel"); /* Create the appliance. */ - create_appliance (inputs, nr_inputs, whitelist, modpath, initrd); + create_appliance (hostcpu, inputs, nr_inputs, whitelist, modpath, + initrd, appliance, writer); if (verbose) print_timestamped_message ("finished creating appliance"); exit (EXIT_SUCCESS); } - -/* Compute Y - X and return the result in milliseconds. - * Approximately the same as this code: - * http://www.mpp.mpg.de/~huber/util/timevaldiff.c - */ -static int64_t -timeval_diff (const struct timeval *x, const struct timeval *y) -{ - int64_t msec; - - msec = (y->tv_sec - x->tv_sec) * 1000; - msec += (y->tv_usec - x->tv_usec) / 1000; - return msec; -} - -static void -print_timestamped_message (const char *fs, ...) -{ - struct timeval tv; - gettimeofday (&tv, NULL); - - va_list args; - char *msg; - int err; - - va_start (args, fs); - err = vasprintf (&msg, fs, args); - va_end (args); - - if (err < 0) return; - - fprintf (stderr, "supermin helper [%05" PRIi64 "ms] %s\n", - timeval_diff (&start_t, &tv), msg); - - free (msg); -} - -static char **read_dir (const char *dir); -static char **filter (char **strings, int (*)(const char *)); -static char **filter_fnmatch (char **strings, const char *patt, int flags); -static char **filter_notmatching_substring (char **strings, const char *sub); -static void sort (char **strings, int (*compare) (const void *, const void *)); -static int isdir (const char *path); - -static int -reverse_filevercmp (const void *p1, const void *p2) -{ - const char *s1 = * (char * const *) p1; - const char *s2 = * (char * const *) p2; - - /* Note, arguments are reversed to achieve a reverse sort. */ - return filevercmp (s2, s1); -} - -static char * -get_modpath (const char *kernel_name) -{ - /* Ignore "vmlinuz-" at the beginning of the kernel name. */ - const char *version = &kernel_name[8]; - - /* /lib/modules/ */ - char *modpath = xasprintf (MODULESDIR "/%s", version); - if (!modpath) { - perror ("xasprintf"); - exit (EXIT_FAILURE); - } - - return modpath; -} - -/* kernel_name is "vmlinuz-*". Check if there is a corresponding - * module path in /lib/modules. - */ -static int -has_modpath (const char *kernel_name) -{ - char *modpath = get_modpath (kernel_name); - - if (verbose) - fprintf (stderr, "checking modpath %s is a directory\n", modpath); - - int r = isdir (modpath); - - if (r) { - if (verbose) - fprintf (stderr, "picked %s because modpath %s exists\n", - kernel_name, modpath); - free (modpath); - return 1; - } - else { - free (modpath); - return 0; - } -} - -/* Create the kernel. This chooses an appropriate kernel and makes a - * symlink to it. - * - * Look for the most recent kernel named vmlinuz-*.* which has a - * corresponding directory in /lib/modules/. If the architecture is - * x86, look for any x86 kernel. - * - * RHEL 5 didn't append the arch to the kernel name, so look for - * kernels without arch second. - * - * If no suitable kernel can be found, exit with an error. - * - * This function returns the module path (ie. /lib/modules/). - */ -static const char * -create_kernel (const char *hostcpu, const char *kernel) -{ - char **all_files = read_dir (KERNELDIR); - - /* In original: ls -1dvr /boot/vmlinuz-*.$arch* 2>/dev/null | grep -v xen */ - const char *patt; - if (hostcpu[0] == 'i' && hostcpu[2] == '8' && hostcpu[3] == '6' && - hostcpu[4] == '\0') - patt = "vmlinuz-*.i?86*"; - else - patt = xasprintf ("vmlinuz-*.%s*", hostcpu); - - char **candidates; - candidates = filter_fnmatch (all_files, patt, FNM_NOESCAPE); - candidates = filter_notmatching_substring (candidates, "xen"); - candidates = filter (candidates, has_modpath); - - if (candidates[0] == NULL) { - /* In original: ls -1dvr /boot/vmlinuz-* 2>/dev/null | grep -v xen */ - patt = "vmlinuz-*"; - candidates = filter_fnmatch (all_files, patt, FNM_NOESCAPE); - candidates = filter_notmatching_substring (candidates, "xen"); - candidates = filter (candidates, has_modpath); - - if (candidates[0] == NULL) - goto no_kernels; - } - - sort (candidates, reverse_filevercmp); - - /* Choose the first candidate. */ - char *tmp = xasprintf (KERNELDIR "/%s", candidates[0]); - - if (verbose) - fprintf (stderr, "creating symlink %s -> %s\n", kernel, tmp); - - if (symlink (tmp, kernel) == -1) - error (EXIT_FAILURE, errno, "symlink kernel"); - - free (tmp); - - return get_modpath (candidates[0]); - - /* Print more diagnostics here than the old script did. */ - no_kernels: - fprintf (stderr, - "febootstrap-supermin-helper: failed to find a suitable kernel.\n" - "I looked for kernels in " KERNELDIR " and modules in " MODULESDIR - ".\n" - "If this is a Xen guest, and you only have Xen domU kernels\n" - "installed, try installing a fullvirt kernel (only for\n" - "febootstrap use, you shouldn't boot the Xen guest with it).\n"); - exit (EXIT_FAILURE); -} - -static void iterate_inputs (char **inputs, int nr_inputs); -static void iterate_input_directory (const char *dirname, int dirfd); -static void write_kernel_modules (const char *whitelist, const char *modpath); -static void write_hostfiles (const char *hostfiles_file); -static void write_to_fd (const void *buffer, size_t len); -static void write_file_to_fd (const char *filename); -static void write_file_len_to_fd (const char *filename, size_t len); -static void write_padding (size_t len); -static char **load_file (const char *filename); -static void cpio_append_fts_entry (FTSENT *entry); -static void cpio_append_stat (const char *filename, struct stat *); -static void cpio_append (const char *filename); -static void cpio_append_trailer (void); - -static int out_fd = -1; -static off_t out_offset = 0; - -/* Create the appliance. - * - * The initrd consists of these components concatenated together: - * - * (1) The base skeleton appliance that we constructed at build time. - * format = plain cpio - * (2) The host files which match wildcards in *.supermin.hostfiles. - * input format = plain text, output format = plain cpio - * (3) The modules from modpath which are on the module whitelist. - * output format = plain cpio - * - * The original shell script used the external cpio program to create - * parts (2) and (3), but we have decided it's going to be faster if - * we just write out the data outselves. The reasons are that - * external cpio is slow (particularly when used with SELinux because - * it does 512 byte reads), and the format that we're writing is - * narrow and well understood, because we only care that the Linux - * kernel can read it. - * - * This version contains some improvements over the C version written - * for libguestfs, in that we can have multiple base images (or - * hostfiles) or use a directory to store these files. - */ -static void -create_appliance (char **inputs, int nr_inputs, - const char *whitelist, - const char *modpath, - const char *initrd) -{ - out_fd = open (initrd, O_WRONLY | O_CREAT | O_TRUNC | O_NOCTTY, 0644); - if (out_fd == -1) - error (EXIT_FAILURE, errno, "open: %s", initrd); - out_offset = 0; - - iterate_inputs (inputs, nr_inputs); - - /* Kernel modules (3). */ - write_kernel_modules (whitelist, modpath); - - cpio_append_trailer (); - - /* Finish off and close output file. */ - if (close (out_fd) == -1) - error (EXIT_FAILURE, errno, "close: %s", initrd); -} - -/* Iterate over the inputs to find out what they are, visiting - * directories if specified. - */ -static void -iterate_inputs (char **inputs, int nr_inputs) -{ - int i; - for (i = 0; i < nr_inputs; ++i) { - if (verbose) - print_timestamped_message ("visiting %s", inputs[i]); - - int fd = open (inputs[i], O_RDONLY); - if (fd == -1) - error (EXIT_FAILURE, errno, "open: %s", inputs[i]); - - struct stat statbuf; - if (fstat (fd, &statbuf) == -1) - error (EXIT_FAILURE, errno, "fstat: %s", inputs[i]); - - /* Directory? */ - if (S_ISDIR (statbuf.st_mode)) - iterate_input_directory (inputs[i], fd); - else if (S_ISREG (statbuf.st_mode)) { - /* Is it a cpio file? */ - char buf[6]; - if (read (fd, buf, 6) == 6 && memcmp (buf, "070701", 6) == 0) - /* Yes, a cpio file. This is a skeleton appliance, case (1). */ - write_file_to_fd (inputs[i]); - else - /* No, must be hostfiles, case (2). */ - write_hostfiles (inputs[i]); - } - else - error (EXIT_FAILURE, 0, "%s: input is not a regular file or directory", - inputs[i]); - - close (fd); - } -} - -static void -iterate_input_directory (const char *dirname, int dirfd) -{ - char path[PATH_MAX]; - strcpy (path, dirname); - size_t len = strlen (dirname); - path[len++] = '/'; - - char *inputs[] = { path }; - - DIR *dir = fdopendir (dirfd); - if (dir == NULL) - error (EXIT_FAILURE, errno, "fdopendir: %s", dirname); - - struct dirent *d; - while ((errno = 0, d = readdir (dir)) != NULL) { - if (d->d_name[0] == '.') /* ignore ., .. and any hidden files. */ - continue; - - strcpy (&path[len], d->d_name); - iterate_inputs (inputs, 1); - } - - if (errno != 0) - error (EXIT_FAILURE, errno, "readdir: %s", dirname); - - if (closedir (dir) == -1) - error (EXIT_FAILURE, errno, "closedir: %s", dirname); -} - -/* Copy kernel modules. - * - * Find every file under modpath. - * - * Exclude all *.ko files, *except* ones which match names in - * the whitelist (which may contain wildcards). Include all - * other files. - * - * Add chosen files to the output. - * - * whitelist_file may be NULL, to include ALL kernel modules. - */ -static void -write_kernel_modules (const char *whitelist_file, const char *modpath) -{ - char **whitelist = NULL; - if (whitelist_file != NULL) - whitelist = load_file (whitelist_file); - - char *paths[2] = { (char *) modpath, NULL }; - FTS *fts = fts_open (paths, FTS_COMFOLLOW|FTS_PHYSICAL, NULL); - if (fts == NULL) - error (EXIT_FAILURE, errno, "write_kernel_modules: fts_open: %s", modpath); - - for (;;) { - errno = 0; - FTSENT *entry = fts_read (fts); - if (entry == NULL && errno != 0) - error (EXIT_FAILURE, errno, "write_kernel_modules: fts_read: %s", modpath); - if (entry == NULL) - break; - - /* Ignore directories being visited in post-order. */ - if (entry->fts_info & FTS_DP) - continue; - - /* Is it a *.ko file? */ - if (entry->fts_namelen >= 3 && - entry->fts_name[entry->fts_namelen-3] == '.' && - entry->fts_name[entry->fts_namelen-2] == 'k' && - entry->fts_name[entry->fts_namelen-1] == 'o') { - if (whitelist) { - /* Is it a *.ko file which is on the whitelist? */ - size_t j; - for (j = 0; whitelist[j] != NULL; ++j) { - int r; - r = fnmatch (whitelist[j], entry->fts_name, 0); - if (r == 0) { - /* It's on the whitelist, so include it. */ - if (verbose >= 2) - fprintf (stderr, "including kernel module %s (matches whitelist entry %s)\n", - entry->fts_name, whitelist[j]); - cpio_append_fts_entry (entry); - break; - } else if (r != FNM_NOMATCH) - error (EXIT_FAILURE, 0, "internal error: fnmatch ('%s', '%s', %d) returned unexpected non-zero value %d\n", - whitelist[j], entry->fts_name, 0, r); - } /* for (j) */ - } else { /* whitelist == NULL, always include */ - if (verbose >= 2) - fprintf (stderr, "including kernel module %s\n", entry->fts_name); - cpio_append_fts_entry (entry); - } - } else - /* It's some other sort of file, or a directory, always include. */ - cpio_append_fts_entry (entry); - } - - if (fts_close (fts) == -1) - error (EXIT_FAILURE, errno, "write_kernel_modules: fts_close: %s", modpath); -} - -/* Copy the host files. - * - * Read the list of entries in hostfiles (which may contain - * wildcards). Look them up in the filesystem, and add those files - * that exist. Ignore any files that don't exist or are not readable. - */ -static void -write_hostfiles (const char *hostfiles_file) -{ - char **hostfiles = load_file (hostfiles_file); - - /* Hostfiles list can contain "." before each path - ignore it. - * It also contains each directory name before we enter it. But - * we don't read that until we see a wildcard for that directory. - */ - size_t i, j; - for (i = 0; hostfiles[i] != NULL; ++i) { - char *hostfile = hostfiles[i]; - if (hostfile[0] == '.') - hostfile++; - - struct stat statbuf; - - /* Is it a wildcard? */ - if (strchr (hostfile, '*') || strchr (hostfile, '?')) { - char *dirname = xstrdup (hostfile); - char *patt = strrchr (dirname, '/'); - assert (patt); - *patt++ = '\0'; - - char **files = read_dir (dirname); - files = filter_fnmatch (files, patt, FNM_NOESCAPE); - - /* Add matching files. */ - for (j = 0; files[j] != NULL; ++j) { - char *tmp = xasprintf ("%s/%s", dirname, files[j]); - - if (verbose >= 2) - fprintf (stderr, "including host file %s (matches %s)\n", tmp, patt); - - cpio_append (tmp); - - free (tmp); - } - } - /* Else does this file/directory/whatever exist? */ - else if (lstat (hostfile, &statbuf) == 0) { - if (verbose >= 2) - fprintf (stderr, "including host file %s (directly referenced)\n", - hostfile); - - cpio_append_stat (hostfile, &statbuf); - } /* Ignore files that don't exist. */ - } -} - -/*----------*/ -/* Helper functions. */ - -static void -add_string (char ***argv, size_t *n_used, size_t *n_alloc, const char *str) -{ - char *new_str; - - if (*n_used >= *n_alloc) - *argv = x2nrealloc (*argv, n_alloc, sizeof (char *)); - - if (str) - new_str = xstrdup (str); - else - new_str = NULL; - - (*argv)[*n_used] = new_str; - - (*n_used)++; -} - -static size_t -count_strings (char *const *argv) -{ - size_t argc; - - for (argc = 0; argv[argc] != NULL; ++argc) - ; - return argc; -} - -struct dir_cache { - char *path; - char **files; -}; - -static size_t -dir_cache_hash (void const *x, size_t table_size) -{ - struct dir_cache const *p = x; - return hash_pjw (p->path, table_size); -} - -static bool -dir_cache_compare (void const *x, void const *y) -{ - struct dir_cache const *p = x; - struct dir_cache const *q = y; - return strcmp (p->path, q->path) == 0; -} - -/* Read a directory into a list of strings. - * - * Previously looked up directories are cached and returned quickly, - * saving some considerable amount of time compared to reading the - * directory over again. However this means you really must not - * alter the array of strings that are returned. - * - * Returns an empty list if the directory cannot be opened. - */ -static char ** -read_dir (const char *name) -{ - static Hash_table *ht = NULL; - - if (!ht) - ht = hash_initialize (1024, NULL, dir_cache_hash, dir_cache_compare, NULL); - - struct dir_cache key = { .path = (char *) name }; - struct dir_cache *p = hash_lookup (ht, &key); - if (p) - return p->files; - - char **files = NULL; - size_t n_used = 0, n_alloc = 0; - - DIR *dir = opendir (name); - if (!dir) { - /* If it fails to open, that's OK, skip to the end. */ - /*perror (name);*/ - goto done; - } - - for (;;) { - errno = 0; - struct dirent *d = readdir (dir); - if (d == NULL) { - if (errno != 0) - /* But if it fails here, after opening and potentially reading - * part of the directory, that's a proper failure - inform the - * user and exit. - */ - error (EXIT_FAILURE, errno, "%s", name); - break; - } - - add_string (&files, &n_used, &n_alloc, d->d_name); - } - - if (closedir (dir) == -1) - error (EXIT_FAILURE, errno, "closedir: %s", name); - - done: - /* NULL-terminate the array. */ - add_string (&files, &n_used, &n_alloc, NULL); - - /* Add it to the hash for next time. */ - p = xmalloc (sizeof *p); - p->path = (char *) name; - p->files = files; - p = hash_insert (ht, p); - assert (p != NULL); - - return files; -} - -/* Filter a list of strings, returning only those where f(s) != 0. */ -static char ** -filter (char **strings, int (*f) (const char *)) -{ - char **out = NULL; - size_t n_used = 0, n_alloc = 0; - - int i; - for (i = 0; strings[i] != NULL; ++i) { - if (f (strings[i]) != 0) - add_string (&out, &n_used, &n_alloc, strings[i]); - } - - add_string (&out, &n_used, &n_alloc, NULL); - return out; -} - -/* Filter a list of strings and return only those matching the wildcard. */ -static char ** -filter_fnmatch (char **strings, const char *patt, int flags) -{ - char **out = NULL; - size_t n_used = 0, n_alloc = 0; - - int i, r; - for (i = 0; strings[i] != NULL; ++i) { - r = fnmatch (patt, strings[i], flags); - if (r == 0) - add_string (&out, &n_used, &n_alloc, strings[i]); - else if (r != FNM_NOMATCH) - error (EXIT_FAILURE, 0, "internal error: fnmatch ('%s', '%s', %d) returned unexpected non-zero value %d\n", - patt, strings[i], flags, r); - } - - add_string (&out, &n_used, &n_alloc, NULL); - return out; -} - -/* Filter a list of strings and return only those which DON'T contain sub. */ -static char ** -filter_notmatching_substring (char **strings, const char *sub) -{ - char **out = NULL; - size_t n_used = 0, n_alloc = 0; - - int i; - for (i = 0; strings[i] != NULL; ++i) { - if (strstr (strings[i], sub) == NULL) - add_string (&out, &n_used, &n_alloc, strings[i]); - } - - add_string (&out, &n_used, &n_alloc, NULL); - return out; -} - -/* Sort a list of strings, in place, with the comparison function supplied. */ -static void -sort (char **strings, int (*compare) (const void *, const void *)) -{ - qsort (strings, count_strings (strings), sizeof (char *), compare); -} - -/* Return true iff path exists and is a directory. This version - * follows symlinks. - */ -static int -isdir (const char *path) -{ - struct stat statbuf; - - if (stat (path, &statbuf) == -1) - return 0; - - return S_ISDIR (statbuf.st_mode); -} - -/* Copy contents of buffer to out_fd and keep out_offset correct. */ -static void -write_to_fd (const void *buffer, size_t len) -{ - if (full_write (out_fd, buffer, len) != len) - error (EXIT_FAILURE, errno, "write"); - out_offset += len; -} - -/* Copy contents of file to out_fd. */ -static void -write_file_to_fd (const char *filename) -{ - char buffer[BUFFER_SIZE]; - int fd2; - ssize_t r; - - if (verbose >= 2) - fprintf (stderr, "write_file_to_fd %s -> %d\n", filename, out_fd); - - fd2 = open (filename, O_RDONLY); - if (fd2 == -1) - error (EXIT_FAILURE, errno, "open: %s", filename); - for (;;) { - r = read (fd2, buffer, sizeof buffer); - if (r == 0) - break; - if (r == -1) { - if (errno == EAGAIN || errno == EWOULDBLOCK || errno == EINTR) - continue; - error (EXIT_FAILURE, errno, "read: %s", filename); - } - write_to_fd (buffer, r); - } - - if (close (fd2) == -1) - error (EXIT_FAILURE, errno, "close: %s", filename); -} - -/* Copy file of given length to output, and fail if the file has - * changed size. - */ -static void -write_file_len_to_fd (const char *filename, size_t len) -{ - char buffer[BUFFER_SIZE]; - size_t count = 0; - - if (verbose >= 2) - fprintf (stderr, "write_file_to_fd %s -> %d\n", filename, out_fd); - - int fd2 = open (filename, O_RDONLY); - if (fd2 == -1) - error (EXIT_FAILURE, errno, "open: %s", filename); - for (;;) { - ssize_t r = read (fd2, buffer, sizeof buffer); - if (r == 0) - break; - if (r == -1) { - if (errno == EAGAIN || errno == EWOULDBLOCK || errno == EINTR) - continue; - error (EXIT_FAILURE, errno, "read: %s", filename); - } - write_to_fd (buffer, r); - count += r; - if (count > len) - error (EXIT_FAILURE, 0, "write_file_len_to_fd: %s: file has increased in size\n", filename); - } - - if (close (fd2) == -1) - error (EXIT_FAILURE, errno, "close: %s", filename); - - if (count != len) - error (EXIT_FAILURE, 0, "febootstrap-supermin-helper: write_file_len_to_fd: %s: file has changed size\n", filename); -} - -/* Load in a file, returning a list of lines. */ -static char ** -load_file (const char *filename) -{ - char **lines = 0; - size_t n_used = 0, n_alloc = 0; - - FILE *fp; - fp = fopen (filename, "r"); - if (fp == NULL) - error (EXIT_FAILURE, errno, "fopen: %s", filename); - - char line[4096]; - while (fgets (line, sizeof line, fp)) { - size_t len = strlen (line); - if (len > 0 && line[len-1] == '\n') - line[len-1] = '\0'; - add_string (&lines, &n_used, &n_alloc, line); - } - - add_string (&lines, &n_used, &n_alloc, NULL); - return lines; -} - -/* Append the file pointed to by FTSENT to the cpio output. */ -static void -cpio_append_fts_entry (FTSENT *entry) -{ - if (entry->fts_info & FTS_NS || entry->fts_info & FTS_NSOK) - cpio_append (entry->fts_path); - else - cpio_append_stat (entry->fts_path, entry->fts_statp); -} - -/* Append the file named 'filename' to the cpio output. */ -static void -cpio_append (const char *filename) -{ - struct stat statbuf; - - if (lstat (filename, &statbuf) == -1) - error (EXIT_FAILURE, errno, "lstat: %s", filename); - cpio_append_stat (filename, &statbuf); -} - -/* Append the file to the cpio output. */ -#define PADDING(len) ((((len) + 3) & ~3) - (len)) - -#define CPIO_HEADER_LEN (6 + 13*8) - -static void -cpio_append_stat (const char *filename, struct stat *statbuf) -{ - const char *orig_filename = filename; - - if (*filename == '/') - filename++; - if (*filename == '\0') - filename = "."; - - if (verbose >= 2) - fprintf (stderr, "cpio_append_stat %s 0%o -> %d\n", - orig_filename, statbuf->st_mode, out_fd); - - /* Regular files and symlinks are the only ones that have a "body" - * in this cpio entry. - */ - int has_body = S_ISREG (statbuf->st_mode) || S_ISLNK (statbuf->st_mode); - - size_t len = strlen (filename) + 1; - - char header[CPIO_HEADER_LEN + 1]; - snprintf (header, sizeof header, - "070701" /* magic */ - "%08X" /* inode */ - "%08X" /* mode */ - "%08X" "%08X" /* uid, gid */ - "%08X" /* nlink */ - "%08X" /* mtime */ - "%08X" /* file length */ - "%08X" "%08X" /* device holding file major, minor */ - "%08X" "%08X" /* for specials, device major, minor */ - "%08X" /* name length (including \0 byte) */ - "%08X", /* checksum (not used by the kernel) */ - (unsigned) statbuf->st_ino, statbuf->st_mode, - statbuf->st_uid, statbuf->st_gid, - (unsigned) statbuf->st_nlink, (unsigned) statbuf->st_mtime, - has_body ? (unsigned) statbuf->st_size : 0, - major (statbuf->st_dev), minor (statbuf->st_dev), - major (statbuf->st_rdev), minor (statbuf->st_rdev), - (unsigned) len, 0); - - /* Write the header. */ - write_to_fd (header, CPIO_HEADER_LEN); - - /* Follow with the filename, and pad it. */ - write_to_fd (filename, len); - size_t padding_len = PADDING (CPIO_HEADER_LEN + len); - write_padding (padding_len); - - /* Follow with the file or symlink content, and pad it. */ - if (has_body) { - if (S_ISREG (statbuf->st_mode)) - write_file_len_to_fd (orig_filename, statbuf->st_size); - else if (S_ISLNK (statbuf->st_mode)) { - char tmp[PATH_MAX]; - if (readlink (orig_filename, tmp, sizeof tmp) == -1) - error (EXIT_FAILURE, errno, "readlink: %s", orig_filename); - write_to_fd (tmp, statbuf->st_size); - } - - padding_len = PADDING (statbuf->st_size); - write_padding (padding_len); - } -} - -/* CPIO voodoo. */ -static void -cpio_append_trailer (void) -{ - struct stat statbuf; - memset (&statbuf, 0, sizeof statbuf); - statbuf.st_nlink = 1; - cpio_append_stat ("TRAILER!!!", &statbuf); - - /* CPIO seems to pad up to the next block boundary, ie. up to - * the next 512 bytes. - */ - write_padding (((out_offset + 511) & ~511) - out_offset); - assert ((out_offset & 511) == 0); -} - -/* Write 'len' bytes of zeroes out. */ -static void -write_padding (size_t len) -{ - static const char buffer[512] = { 0 }; - - while (len > 0) { - size_t n = len < sizeof buffer ? len : sizeof buffer; - write_to_fd (buffer, n); - len -= n; - } -}