libreboot-utils: unified error handling

i now use a singleton hook function per program:
nvmutil, mkhtemp and lottery

call this at the startup of your program:

(void) errhook(exit_cleanup);

then provide that function. make it static,
so that each program has its own version.

if you're writing a program that handles lots
of files for example, and you want to do certain
cleanup on exit (including error exit), this can
be quite useful.

Signed-off-by: Leah Rowe <leah@libreboot.org>

14 files changed, 182 insertions, 186 deletions

diff --git a/util/libreboot-utils/include/common.h b/util/libreboot-utils/include/common.h
index 652b8c08..9ec8a0e3 100644
--- a/util/libreboot-utils/include/common.h
+++ b/util/libreboot-utils/include/common.h
@@ -225,10 +225,12 @@ int fchmod(int fd, mode_t mode);
 /* command table
  */
 
+typedef void (*func_t)(void);
+
 struct commands {
 	size_t chk;
 	char *str;
-	void (*run)(void);
+	func_t run;
 	int argc;
 	unsigned char arg_part;
 	unsigned char chksum_read;
@@ -488,12 +490,11 @@ int try_err(int loop_err, int errval);
  */
 
 void usage(void);
-void err_no_cleanup(int stfu, int nvm_errval, const char *msg, ...);
-void b0rk(int nvm_errval, const char *msg, ...);
-int exit_cleanup(void);
+void err_exit(int nvm_errval, const char *msg, ...);
+func_t errhook(func_t ptr); /* hook function for cleanup on err */
 const char *getnvmprogname(void);
-
-void err_mkhtemp(int stfu, int errval, const char *msg, ...);
+void no_op(void);
+void err_mkhtemp(int errval, const char *msg, ...);
 
 /* libc hardening
  */
diff --git a/util/libreboot-utils/lib/checksum.c b/util/libreboot-utils/lib/checksum.c
index 9a041989..97b0efca 100644
--- a/util/libreboot-utils/lib/checksum.c
+++ b/util/libreboot-utils/lib/checksum.c
@@ -59,10 +59,10 @@ read_checksums(void)
 	if (_num_invalid >= _max_invalid) {
 
 		if (_max_invalid == 1)
-			b0rk(ECANCELED, "%s: part %lu has a bad checksum",
+			err_exit(ECANCELED, "%s: part %lu has a bad checksum",
 			    f->fname, (size_t)f->part);
 
-		b0rk(ECANCELED, "%s: No valid checksum found in file",
+		err_exit(ECANCELED, "%s: No valid checksum found in file",
 		    f->fname);
 	}
 }
diff --git a/util/libreboot-utils/lib/command.c b/util/libreboot-utils/lib/command.c
index c7048a23..d0f783dd 100644
--- a/util/libreboot-utils/lib/command.c
+++ b/util/libreboot-utils/lib/command.c
@@ -46,27 +46,27 @@ sanitize_command_index(size_t c)
 	check_command_num(c);
 
 	if (cmd->argc < 3)
-		b0rk(EINVAL, "cmd index %lu: argc below 3, %d",
+		err_exit(EINVAL, "cmd index %lu: argc below 3, %d",
 		    (size_t)c, cmd->argc);
 
 	if (cmd->str == NULL)
-		b0rk(EINVAL, "cmd index %lu: NULL str",
+		err_exit(EINVAL, "cmd index %lu: NULL str",
 		    (size_t)c);
 
 	if (*cmd->str == '\0')
-		b0rk(EINVAL, "cmd index %lu: empty str",
+		err_exit(EINVAL, "cmd index %lu: empty str",
 		    (size_t)c);
 
 	if (slen(cmd->str, MAX_CMD_LEN +1, &rval) < 0)
-		b0rk(errno, "Could not get command length");
+		err_exit(errno, "Could not get command length");
 
 	if (rval > MAX_CMD_LEN) {
-		b0rk(EINVAL, "cmd index %lu: str too long: %s",
+		err_exit(EINVAL, "cmd index %lu: str too long: %s",
 		    (size_t)c, cmd->str);
 	}
 
 	if (cmd->run == NULL)
-		b0rk(EINVAL, "cmd index %lu: cmd ptr null",
+		err_exit(EINVAL, "cmd index %lu: cmd ptr null",
 		    (size_t)c);
 
 	check_bin(cmd->arg_part, "cmd.arg_part");
@@ -80,19 +80,19 @@ sanitize_command_index(size_t c)
 	case NVM_SIZE:
 		break;
 	default:
-		b0rk(EINVAL, "Unsupported rw_size: %lu",
+		err_exit(EINVAL, "Unsupported rw_size: %lu",
 		    (size_t)gbe_rw_size);
 	}
 
 	if (gbe_rw_size > GBE_PART_SIZE)
-		b0rk(EINVAL, "rw_size larger than GbE part: %lu",
+		err_exit(EINVAL, "rw_size larger than GbE part: %lu",
 		    (size_t)gbe_rw_size);
 
 	_flag = (cmd->flags & O_ACCMODE);
 
 	if (_flag != O_RDONLY &&
 	    _flag != O_RDWR)
-		b0rk(EINVAL, "invalid cmd.flags setting");
+		err_exit(EINVAL, "invalid cmd.flags setting");
 }
 
 void
@@ -110,7 +110,7 @@ set_cmd(int argc, char *argv[])
 		cmd = x->cmd[c].str;
 
 		if (scmp(argv[2], cmd, MAX_CMD_LEN, &rval) < 0)
-			err_no_cleanup(0, EINVAL,
+			err_exit(EINVAL,
 			    "could not compare command strings");
 		if (rval != 0)
 			continue; /* not the right command */
@@ -123,7 +123,7 @@ set_cmd(int argc, char *argv[])
 			return;
 		}
 
-		err_no_cleanup(0, EINVAL,
+		err_exit(EINVAL,
 		    "Too few args on command '%s'", cmd);
 	}
 
@@ -148,11 +148,11 @@ set_cmd_args(int argc, char *argv[])
 	/* Maintainer bug
 	 */
 	if (cmd->arg_part && argc < 4)
-		b0rk(EINVAL,
+		err_exit(EINVAL,
 		    "arg_part set for command that needs argc4");
 
 	if (cmd->arg_part && i == CMD_SETMAC)
-		b0rk(EINVAL,
+		err_exit(EINVAL,
 		    "arg_part set on CMD_SETMAC");
 
 	if (i == CMD_SETMAC) {
@@ -174,13 +174,13 @@ conv_argv_part_num(const char *part_str)
 	unsigned char ch;
 
 	if (part_str[0] == '\0' || part_str[1] != '\0')
-		b0rk(EINVAL, "Partnum string '%s' wrong length", part_str);
+		err_exit(EINVAL, "Partnum string '%s' wrong length", part_str);
 
 	/* char signedness is implementation-defined
 	 */
 	ch = (unsigned char)part_str[0];
 	if (ch < '0' || ch > '1')
-		b0rk(EINVAL, "Bad part number (%c)", ch);
+		err_exit(EINVAL, "Bad part number (%c)", ch);
 
 	return (size_t)(ch - '0');
 }
@@ -189,7 +189,7 @@ void
 check_command_num(size_t c)
 {
 	if (!valid_command(c))
-		b0rk(EINVAL, "Invalid run_cmd arg: %lu",
+		err_exit(EINVAL, "Invalid run_cmd arg: %lu",
 		    (size_t)c);
 }
 
@@ -205,7 +205,7 @@ valid_command(size_t c)
 	cmd = &x->cmd[c];
 
 	if (c != cmd->chk)
-		b0rk(EINVAL,
+		err_exit(EINVAL,
 		    "Invalid cmd chk value (%lu) vs arg: %lu",
 		    cmd->chk, c);
 
@@ -240,10 +240,10 @@ parse_mac_string(void)
 	size_t rval;
 
 	if (slen(x->mac.str, 18, &rval) < 0)
-		b0rk(EINVAL, "Could not determine MAC length");
+		err_exit(EINVAL, "Could not determine MAC length");
 
 	if (rval != 17)
-		b0rk(EINVAL, "MAC address is the wrong length");
+		err_exit(EINVAL, "MAC address is the wrong length");
 
 	memset(mac->mac_buf, 0, sizeof(mac->mac_buf));
 
@@ -251,10 +251,10 @@ parse_mac_string(void)
 		set_mac_byte(mac_byte);
 
 	if ((mac->mac_buf[0] | mac->mac_buf[1] | mac->mac_buf[2]) == 0)
-		b0rk(EINVAL, "Must not specify all-zeroes MAC address");
+		err_exit(EINVAL, "Must not specify all-zeroes MAC address");
 
 	if (mac->mac_buf[0] & 1)
-		b0rk(EINVAL, "Must not specify multicast MAC address");
+		err_exit(EINVAL, "Must not specify multicast MAC address");
 }
 
 void
@@ -272,7 +272,7 @@ set_mac_byte(size_t mac_byte_pos)
 
 	if (mac_str_pos < 15) {
 		if ((separator = mac->str[mac_str_pos + 2]) != ':')
-			b0rk(EINVAL, "Invalid MAC address separator '%c'",
+			err_exit(EINVAL, "Invalid MAC address separator '%c'",
 			    separator);
 	}
 
@@ -294,9 +294,9 @@ set_mac_nib(size_t mac_str_pos,
 
 	if ((hex_num = hextonum(mac_ch)) > 15) {
 		if (hex_num >= 17)
-			b0rk(EIO, "Randomisation failure");
+			err_exit(EIO, "Randomisation failure");
 		else
-			b0rk(EINVAL, "Invalid character '%c'",
+			err_exit(EINVAL, "Invalid character '%c'",
 			    mac->str[mac_str_pos + mac_nib_pos]);
 	}
 
@@ -509,7 +509,7 @@ cat(size_t nff)
 
 	if ((size_t)x->cat != nff) {
 
-		b0rk(ECANCELED, "erroneous call to cat");
+		err_exit(ECANCELED, "erroneous call to cat");
 	}
 
 	fflush(NULL);
@@ -532,12 +532,12 @@ void
 cat_buf(unsigned char *b)
 {
 	if (b == NULL)
-		b0rk(errno, "null pointer in cat command");
+		err_exit(errno, "null pointer in cat command");
 
 	if (rw_file_exact(STDOUT_FILENO, b,
 	    GBE_PART_SIZE, 0, IO_WRITE, LOOP_EAGAIN, LOOP_EINTR,
 	    MAX_ZERO_RW_RETRY, OFF_ERR) < 0)
-		b0rk(errno, "stdout: cat");
+		err_exit(errno, "stdout: cat");
 }
 void
 check_cmd(void (*fn)(void),
@@ -547,7 +547,7 @@ check_cmd(void (*fn)(void),
 	size_t i = x->i;
 
 	if (x->cmd[i].run != fn)
-		b0rk(ECANCELED, "Running %s, but cmd %s is set",
+		err_exit(ECANCELED, "Running %s, but cmd %s is set",
 		    name, x->cmd[i].str);
 
 	/* prevent second command
@@ -559,6 +559,6 @@ check_cmd(void (*fn)(void),
 void
 cmd_helper_err(void)
 {
-	b0rk(ECANCELED,
+	err_exit(ECANCELED,
 	    "Erroneously running command twice");
 }
diff --git a/util/libreboot-utils/lib/file.c b/util/libreboot-utils/lib/file.c
index 3b3e57d8..fbb4e53f 100644
--- a/util/libreboot-utils/lib/file.c
+++ b/util/libreboot-utils/lib/file.c
@@ -73,16 +73,16 @@ void
 xopen(int *fd_ptr, const char *path, int flags, struct stat *st)
 {
 	if ((*fd_ptr = open(path, flags)) < 0)
-		err_no_cleanup(0, errno, "%s", path);
+		err_exit(errno, "%s", path);
 
 	if (fstat(*fd_ptr, st) < 0)
-		err_no_cleanup(0, errno, "%s: stat", path);
+		err_exit(errno, "%s: stat", path);
 
 	if (!S_ISREG(st->st_mode))
-		err_no_cleanup(0, errno, "%s: not a regular file", path);
+		err_exit(errno, "%s: not a regular file", path);
 
 	if (lseek_on_eintr(*fd_ptr, 0, SEEK_CUR, 1, 1) == (off_t)-1)
-		err_no_cleanup(0, errno, "%s: file not seekable", path);
+		err_exit(errno, "%s: file not seekable", path);
 }
 
 int
diff --git a/util/libreboot-utils/lib/io.c b/util/libreboot-utils/lib/io.c
index 1f2064a0..4fa6bf72 100644
--- a/util/libreboot-utils/lib/io.c
+++ b/util/libreboot-utils/lib/io.c
@@ -32,16 +32,16 @@ open_gbe_file(void)
 	    O_NOFOLLOW | O_CLOEXEC | O_NOCTTY, &f->gbe_st);
 
 	if (f->gbe_st.st_nlink > 1)
-		b0rk(EINVAL,
+		err_exit(EINVAL,
 		    "%s: warning: file has multiple (%lu) hard links\n",
 		    f->fname, (size_t)f->gbe_st.st_nlink);
 
 	if (f->gbe_st.st_nlink == 0)
-		b0rk(EIO, "%s: file unlinked while open", f->fname);
+		err_exit(EIO, "%s: file unlinked while open", f->fname);
 
 	_flags = fcntl(f->gbe_fd, F_GETFL);
 	if (_flags == -1)
-		b0rk(errno, "%s: fcntl(F_GETFL)", f->fname);
+		err_exit(errno, "%s: fcntl(F_GETFL)", f->fname);
 
 	/* O_APPEND allows POSIX write() to ignore
 	 * the current write offset and write at EOF,
@@ -49,7 +49,7 @@ open_gbe_file(void)
 	 */
 
 	if (_flags & O_APPEND)
-		b0rk(EIO, "%s: O_APPEND flag", f->fname);
+		err_exit(EIO, "%s: O_APPEND flag", f->fname);
 
 	f->gbe_file_size = f->gbe_st.st_size;
 
@@ -59,11 +59,11 @@ open_gbe_file(void)
 	case SIZE_128KB:
 		break;
 	default:
-		b0rk(EINVAL, "File size must be 8KB, 16KB or 128KB");
+		err_exit(EINVAL, "File size must be 8KB, 16KB or 128KB");
 	}
 
 	if (lock_file(f->gbe_fd, cmd->flags) == -1)
-		b0rk(errno, "%s: can't lock", f->fname);
+		err_exit(errno, "%s: can't lock", f->fname);
 }
 
 void
@@ -98,7 +98,7 @@ read_file(void)
 	    MAX_ZERO_RW_RETRY, OFF_ERR);
 
 	if (_r < 0)
-		b0rk(errno, "%s: read failed", f->fname);
+		err_exit(errno, "%s: read failed", f->fname);
 
 	/* copy to tmpfile
 	 */
@@ -107,34 +107,34 @@ read_file(void)
 	    MAX_ZERO_RW_RETRY, OFF_ERR);
 
 	if (_r < 0)
-		b0rk(errno, "%s: %s: copy failed",
+		err_exit(errno, "%s: %s: copy failed",
 		    f->fname, f->tname);
 
 	/* file size comparison
 	 */
 	if (fstat(f->tmp_fd, &_st) == -1)
-		b0rk(errno, "%s: stat", f->tname);
+		err_exit(errno, "%s: stat", f->tname);
 
 	f->gbe_tmp_size = _st.st_size;
 
 	if (f->gbe_tmp_size != f->gbe_file_size)
-		b0rk(EIO, "%s: %s: not the same size",
+		err_exit(EIO, "%s: %s: not the same size",
 		    f->fname, f->tname);
 
 	/* needs sync, for verification
 	 */
 	if (fsync_on_eintr(f->tmp_fd) == -1)
-		b0rk(errno, "%s: fsync (tmpfile copy)", f->tname);
+		err_exit(errno, "%s: fsync (tmpfile copy)", f->tname);
 
 	_r = rw_file_exact(f->tmp_fd, f->bufcmp, f->gbe_file_size,
 	    0, IO_PREAD, NO_LOOP_EAGAIN, LOOP_EINTR,
 	    MAX_ZERO_RW_RETRY, OFF_ERR);
 
 	if (_r < 0)
-		b0rk(errno, "%s: read failed (cmp)", f->tname);
+		err_exit(errno, "%s: read failed (cmp)", f->tname);
 
 	if (memcmp(f->buf, f->bufcmp, f->gbe_file_size) != 0)
-		b0rk(errno, "%s: %s: read contents differ (pre-test)",
+		err_exit(errno, "%s: %s: read contents differ (pre-test)",
 		    f->fname, f->tname);
 }
 
@@ -152,10 +152,10 @@ write_gbe_file(void)
 		return;
 
 	if (same_file(f->tmp_fd, &f->tmp_st, 0) < 0)
-		b0rk(errno, "%s: file inode/device changed", f->tname);
+		err_exit(errno, "%s: file inode/device changed", f->tname);
 
 	if (same_file(f->gbe_fd, &f->gbe_st, 1) < 0)
-		b0rk(errno, "%s: file has changed", f->fname);
+		err_exit(errno, "%s: file has changed", f->fname);
 
 	update_checksum = cmd->chksum_write;
 
@@ -188,7 +188,7 @@ rw_gbe_file_part(size_t p, int rw_type,
 	gbe_rw_size = cmd->rw_size;
 
 	if (rw_type < IO_PREAD || rw_type > IO_PWRITE)
-		b0rk(errno, "%s: %s: part %lu: invalid rw_type, %d",
+		err_exit(errno, "%s: %s: part %lu: invalid rw_type, %d",
 		    f->fname, rw_type_str, (size_t)p, rw_type);
 
 	mem_offset = gbe_mem_offset(p, rw_type_str);
@@ -198,11 +198,11 @@ rw_gbe_file_part(size_t p, int rw_type,
 	    gbe_rw_size, file_offset, rw_type);
 
 	if (rval == -1)
-		b0rk(errno, "%s: %s: part %lu",
+		err_exit(errno, "%s: %s: part %lu",
 		    f->fname, rw_type_str, (size_t)p);
 
 	if ((size_t)rval != gbe_rw_size)
-		b0rk(EIO, "%s: partial %s: part %lu",
+		err_exit(EIO, "%s: partial %s: part %lu",
 		    f->fname, rw_type_str, (size_t)p);
 }
 
@@ -226,7 +226,7 @@ write_to_gbe_bin(void)
 	 */
 
 	if (fsync_on_eintr(f->tmp_fd) == -1)
-		b0rk(errno, "%s: fsync (pre-verification)",
+		err_exit(errno, "%s: fsync (pre-verification)",
 		    f->tname);
 
 	check_written_part(0);
@@ -235,7 +235,7 @@ write_to_gbe_bin(void)
 	report_io_err_rw();
 
 	if (f->io_err_gbe)
-		b0rk(EIO, "%s: bad write", f->fname);
+		err_exit(EIO, "%s: bad write", f->fname);
 
 	saved_errno = errno;
 
@@ -307,10 +307,10 @@ check_written_part(size_t p)
 	memset(f->pad, 0xff, sizeof(f->pad));
 
 	if (same_file(f->tmp_fd, &f->tmp_st, 0) < 0)
-		b0rk(errno, "%s: file inode/device changed", f->tname);
+		err_exit(errno, "%s: file inode/device changed", f->tname);
 
 	if (same_file(f->gbe_fd, &f->gbe_st, 1) < 0)
-		b0rk(errno, "%s: file changed during write", f->fname);
+		err_exit(errno, "%s: file changed during write", f->fname);
 
 	rval = rw_gbe_file_exact(f->tmp_fd, f->pad,
 	    gbe_rw_size, file_offset, IO_PREAD);
@@ -540,11 +540,11 @@ gbe_x_offset(size_t p, const char *f_op, const char *d_type,
 	off = ((off_t)p) * (off_t)nsize;
 
 	if (off > ncmp - GBE_PART_SIZE)
-		b0rk(ECANCELED, "%s: GbE %s %s out of bounds",
+		err_exit(ECANCELED, "%s: GbE %s %s out of bounds",
 		    f->fname, d_type, f_op);
 
 	if (off != 0 && off != ncmp >> 1)
-		b0rk(ECANCELED, "%s: GbE %s %s at bad offset",
+		err_exit(ECANCELED, "%s: GbE %s %s at bad offset",
 		    f->fname, d_type, f_op);
 
 	return off;
diff --git a/util/libreboot-utils/lib/num.c b/util/libreboot-utils/lib/num.c
index f53f0cee..66fc26f1 100644
--- a/util/libreboot-utils/lib/num.c
+++ b/util/libreboot-utils/lib/num.c
@@ -51,6 +51,6 @@ void
 check_bin(size_t a, const char *a_name)
 {
 	if (a > 1)
-		err_no_cleanup(0, EINVAL, "%s must be 0 or 1, but is %lu",
+		err_exit(EINVAL, "%s must be 0 or 1, but is %lu",
 		    a_name, (size_t)a);
 }
diff --git a/util/libreboot-utils/lib/rand.c b/util/libreboot-utils/lib/rand.c
index 863ace17..3ca19d0c 100644
--- a/util/libreboot-utils/lib/rand.c
+++ b/util/libreboot-utils/lib/rand.c
@@ -77,7 +77,7 @@ rsize(size_t n)
 {
 	size_t rval = SIZE_MAX;
 	if (!n)
-		err_no_cleanup(0, EFAULT, "rsize: division by zero");
+		err_exit(EFAULT, "rsize: division by zero");
 
 	/* rejection sampling (clamp rand to eliminate modulo bias) */
 	for (; rval >= SIZE_MAX - (SIZE_MAX % n); rset(&rval, sizeof(rval)));
@@ -92,13 +92,13 @@ mkrstr(size_t n) /* emulates spkmodem-decode */
 	size_t i;
 
 	if (n == 0)
-		err_no_cleanup(0, EPERM, "mkrbuf: zero-byte request");
+		err_exit(EPERM, "mkrbuf: zero-byte request");
 
 	if (n >= SIZE_MAX - 1)
-		err_no_cleanup(0, EOVERFLOW, "mkrbuf: overflow");
+		err_exit(EOVERFLOW, "mkrbuf: overflow");
 
 	if (if_err((s = mkrbuf(n + 1)) == NULL, EFAULT))
-		err_no_cleanup(0, EFAULT, "mkrstr: null");
+		err_exit(EFAULT, "mkrstr: null");
 
 	for (i = 0; i < n; i++)
 		while(*(s + i) == '\0')
@@ -126,7 +126,7 @@ rset(void *buf, size_t n)
 		goto err;
 
 	if (n == 0)
-		err_no_cleanup(0, EPERM, "rset: zero-byte request");
+		err_exit(EPERM, "rset: zero-byte request");
 
 #if (defined(__OpenBSD__) || defined(__FreeBSD__) || \
     defined(__NetBSD__) || defined(__APPLE__) || \
@@ -181,7 +181,7 @@ err:
     ((USE_URANDOM) > 0)
 	close_no_err(&fd);
 #endif
-	err_no_cleanup(0, ECANCELED,
+	err_exit(ECANCELED,
 	    "Randomisation failure, possibly unsupported in your kernel");
 	exit(EXIT_FAILURE);
 }
diff --git a/util/libreboot-utils/lib/state.c b/util/libreboot-utils/lib/state.c
index 41c851fb..a3cd5b1f 100644
--- a/util/libreboot-utils/lib/state.c
+++ b/util/libreboot-utils/lib/state.c
@@ -4,9 +4,6 @@
  * State machine (singleton) for nvmutil data.
  */
 
-#ifdef __OpenBSD__
-#include <sys/param.h>
-#endif
 #include <sys/types.h>
 #include <sys/stat.h>
 
@@ -98,9 +95,9 @@ xstart(int argc, char *argv[])
 		return &us;
 
 	if (argc < 3)
-		err_no_cleanup(0, EINVAL, "xstart: Too few arguments");
+		err_exit(EINVAL, "xstart: Too few arguments");
 	if (argv == NULL)
-		err_no_cleanup(0, EINVAL, "xstart: NULL argv");
+		err_exit(EINVAL, "xstart: NULL argv");
 	
 	first_run = 0;
 
@@ -113,41 +110,41 @@ xstart(int argc, char *argv[])
 	us.f.tname = NULL;
 
 	if ((realdir = realpath(us.f.fname, NULL)) == NULL)
-		err_no_cleanup(0, errno, "xstart: can't get realpath of %s",
+		err_exit(errno, "xstart: can't get realpath of %s",
 		    us.f.fname);
 
 	if (fs_dirname_basename(realdir, &dir, &base, 0) < 0)
-		err_no_cleanup(0, errno, "xstart: don't know CWD of %s",
+		err_exit(errno, "xstart: don't know CWD of %s",
 		    us.f.fname);
 
 	if ((us.f.base = strdup(base)) == NULL)
-		err_no_cleanup(0, errno, "strdup base");
+		err_exit(errno, "strdup base");
 
 	us.f.dirfd = fs_open(dir,
 	    O_RDONLY | O_DIRECTORY);
 	if (us.f.dirfd < 0)
-		err_no_cleanup(0, errno, "%s: open dir", dir);
+		err_exit(errno, "%s: open dir", dir);
 
 	if (new_tmpfile(&us.f.tmp_fd, &us.f.tname, dir, ".gbe.XXXXXXXXXX") < 0)
-		err_no_cleanup(0, errno, "%s", us.f.tname);
+		err_exit(errno, "%s", us.f.tname);
 
 	if (fs_dirname_basename(us.f.tname,
 	    &tmpdir, &tmpbase_local, 0) < 0)
-		err_no_cleanup(0, errno, "tmp basename");
+		err_exit(errno, "tmp basename");
 
 	us.f.tmpbase = strdup(tmpbase_local);
 	if (us.f.tmpbase == NULL)
-		err_no_cleanup(0, errno, "strdup tmpbase");
+		err_exit(errno, "strdup tmpbase");
 
 	free_and_set_null(&tmpdir);
 
 	if (us.f.tname == NULL)
-		err_no_cleanup(0, errno, "x->f.tname null");
+		err_exit(errno, "x->f.tname null");
 	if (*us.f.tname == '\0')
-		err_no_cleanup(0, errno, "x->f.tname empty");
+		err_exit(errno, "x->f.tname empty");
 
 	if (fstat(us.f.tmp_fd, &us.f.tmp_st) < 0)
-		err_no_cleanup(0, errno, "%s: stat", us.f.tname);
+		err_exit(errno, "%s: stat", us.f.tname);
 
 	memset(us.f.real_buf, 0, sizeof(us.f.real_buf));
 	memset(us.f.bufcmp, 0, sizeof(us.f.bufcmp));
@@ -164,70 +161,7 @@ xstatus(void)
 	struct xstate *x = xstart(0, NULL);
 
 	if (x == NULL)
-		err_no_cleanup(0, EACCES, "NULL pointer to xstate");
+		err_exit(EACCES, "NULL pointer to xstate");
 
 	return x;
 }
-
-void
-b0rk(int nvm_errval, const char *msg, ...)
-{
-	struct xstate *x = xstatus();
-
-	va_list args;
-
-	if (errno == 0)
-		errno = nvm_errval;
-	if (!errno)
-		errno = ECANCELED;
-
-	(void)exit_cleanup();
-
-	if (x != NULL)
-		fprintf(stderr, "%s: ", getnvmprogname());
-
-	va_start(args, msg);
-	vfprintf(stderr, msg, args);
-	va_end(args);
-
-	fprintf(stderr, ": %s\n", strerror(errno));
-
-	exit(EXIT_FAILURE);
-}
-
-int
-exit_cleanup(void)
-{
-	struct xstate *x = xstatus();
-	struct xfile *f;
-
-	int close_err;
-	int saved_errno;
-
-	close_err = 0;
-	saved_errno = errno;
-
-	if (x != NULL) {
-		f = &x->f;
-
-		close_no_err(&f->gbe_fd);
-		close_no_err(&f->tmp_fd);
-		close_no_err(&f->tmp_fd);
-
-		if (f->tname != NULL)
-			if (unlink(f->tname) == -1)
-				close_err = 1;
-
-		close_no_err(&f->dirfd);
-		free_and_set_null(&f->base);
-		free_and_set_null(&f->tmpbase);
-	}
-
-	if (saved_errno)
-		errno = saved_errno;
-
-	if (close_err)
-		return -1;
-
-	return 0;
-}
diff --git a/util/libreboot-utils/lib/string.c b/util/libreboot-utils/lib/string.c
index dd11c039..9e38a9e9 100644
--- a/util/libreboot-utils/lib/string.c
+++ b/util/libreboot-utils/lib/string.c
@@ -40,9 +40,9 @@ vmalloc(void **buf, size_t size)
 	void *rval = NULL;
 
 	if (size >= SIZE_MAX - 1)
-		err_no_cleanup(0, EOVERFLOW, "integer overflow in vmalloc");
+		err_exit(EOVERFLOW, "integer overflow in vmalloc");
 	if (buf == NULL)
-		err_no_cleanup(0, EFAULT, "Bad pointer passed to vmalloc");
+		err_exit(EFAULT, "Bad pointer passed to vmalloc");
 
 	/* lots of programs will
 	 * re-initialise a buffer
@@ -52,14 +52,14 @@ vmalloc(void **buf, size_t size)
 	 * force the programmer to behave
 	 */
 	if (*buf != NULL)
-		err_no_cleanup(0, EFAULT, "Non-null pointer given to vmalloc");
+		err_exit(EFAULT, "Non-null pointer given to vmalloc");
 
 	if (!size)
-		err_no_cleanup(0, EFAULT,
+		err_exit(EFAULT,
 		   "Tried to vmalloc(0) and that is very bad. Fix it now");
 
 	if ((rval = malloc(size)) == NULL)
-		err_no_cleanup(0, errno, "malloc fail in vmalloc");
+		err_exit(errno, "malloc fail in vmalloc");
 
 	return *buf = rval;
 }
@@ -288,12 +288,16 @@ err:
 /* the one for nvmutil state is in state.c */
 /* this one just exits */
 void
-err_no_cleanup(int stfu, int nvm_errval, const char *msg, ...)
+err_exit(int nvm_errval, const char *msg, ...)
 {
 	va_list args;
 	int saved_errno = errno;
 	const char *p;
 
+	func_t err_cleanup = errhook(NULL);
+	err_cleanup();
+	errno = saved_errno;
+
 	if (!errno)
 		saved_errno = errno = ECANCELED;
 
@@ -312,6 +316,37 @@ err_no_cleanup(int stfu, int nvm_errval, const char *msg, ...)
 	exit(EXIT_FAILURE);
 }
 
+/* the err function will
+ * call this upon exit, and
+ * cleanup will be performed
+ * e.g. you might want to
+ * close some files, depending
+ * on your program.
+ * see: err_exit()
+ */
+func_t errhook(func_t ptr)
+{
+	static int set = 0;
+	static func_t hook = NULL;
+
+	if (!set) {
+		set = 1;
+
+		if (ptr == NULL)
+			hook = no_op;
+		else
+			hook = ptr;
+	}
+
+	return hook;
+}
+
+void
+no_op(void)
+{
+	return;
+}
+
 const char *
 getnvmprogname(void)
 {
@@ -366,7 +401,7 @@ xpledgex(const char *promises, const char *execpromises)
 	(void) promises, (void) execpromises, (void) saved_errno;
 #ifdef __OpenBSD__
 	if (pledge(promises, execpromises) == -1)
-		err_no_cleanup(0, errno, "pledge");
+		err_exit(errno, "pledge");
 #endif
 	errno = saved_errno;
 	return 0;
@@ -378,7 +413,7 @@ xunveilx(const char *path, const char *permissions)
 	(void) path, (void) permissions, (void) saved_errno;
 #ifdef __OpenBSD__
 	if (pledge(promises, execpromises) == -1)
-		err_no_cleanup(0, errno, "pledge");
+		err_exit(errno, "pledge");
 #endif
 	errno = saved_errno;
 	return 0;
diff --git a/util/libreboot-utils/lib/usage.c b/util/libreboot-utils/lib/usage.c
index 2b5a93ca..ebec119e 100644
--- a/util/libreboot-utils/lib/usage.c
+++ b/util/libreboot-utils/lib/usage.c
@@ -26,5 +26,5 @@ usage(void)
 	    util, util, util, util,
 	    util, util, util);
 
-	b0rk(EINVAL, "Too few arguments");
+	err_exit(EINVAL, "Too few arguments");
 }
diff --git a/util/libreboot-utils/lib/word.c b/util/libreboot-utils/lib/word.c
index 6563e67a..85e1d88b 100644
--- a/util/libreboot-utils/lib/word.c
+++ b/util/libreboot-utils/lib/word.c
@@ -63,6 +63,6 @@ check_nvm_bound(size_t c, size_t p)
 	check_bin(p, "part number");
 
 	if (c >= NVM_WORDS)
-		b0rk(ECANCELED, "check_nvm_bound: out of bounds %lu",
+		err_exit(ECANCELED, "check_nvm_bound: out of bounds %lu",
 		    (size_t)c);
 }
diff --git a/util/libreboot-utils/lottery.c b/util/libreboot-utils/lottery.c
index fd0728fd..cbe8a871 100644
--- a/util/libreboot-utils/lottery.c
+++ b/util/libreboot-utils/lottery.c
@@ -11,6 +11,9 @@
 #include "include/common.h"
 
 static void
+exit_cleanup(void);
+
+static void
 spew_buf(const void *data, size_t len);
 
 int
@@ -22,6 +25,8 @@ main(int argc, char **argv)
 	(void) argc, (void) argv;
 	xpledgex("stdio", NULL);
 
+	(void) errhook(exit_cleanup);
+
 	buf = mkrbuf(BUFSIZ + 1);
 	if (!memcmp(buf, buf + (BUFSIZ >> 1), BUFSIZ >> 1))
 		same = 1;
@@ -73,3 +78,9 @@ spew_buf(const void *data, size_t len)
 
 	printf("%08zx\n", len);
 }
+
+static void
+exit_cleanup(void)
+{
+	return;
+}
diff --git a/util/libreboot-utils/mkhtemp.c b/util/libreboot-utils/mkhtemp.c
index 32a967d1..5be5a38a 100644
--- a/util/libreboot-utils/mkhtemp.c
+++ b/util/libreboot-utils/mkhtemp.c
@@ -34,6 +34,9 @@
 
 #include "include/common.h"
 
+static void
+exit_cleanup(void);
+
 int
 main(int argc, char *argv[])
 {
@@ -57,10 +60,11 @@ main(int argc, char *argv[])
 
 	int fd = -1;
 	int type = MKHTEMP_FILE;
-	int stfu = 0; /* -q option */
+
+	(void) errhook(exit_cleanup);
 
 	if (lbgetprogname(argv[0]) == NULL)
-		err_no_cleanup(stfu, errno, "could not set progname");
+		err_exit(errno, "could not set progname");
 
 	/* https://man.openbsd.org/pledge.2 */
 	xpledgex("stdio flock rpath wpath cpath", NULL);
@@ -79,7 +83,6 @@ main(int argc, char *argv[])
 
 		case 'q': /* don't print errors */
 			  /* (exit status unchanged) */
-			stfu = 1;
 			break;
 
 		default:
@@ -95,14 +98,14 @@ main(int argc, char *argv[])
 	/* custom template e.g. foo.XXXXXXXXXXXXXXXXXXXXX */
 	if (template != NULL) {	
 		if (slen(template, maxlen, &tlen) < 0)
-			err_no_cleanup(stfu, EINVAL,
+			err_exit(EINVAL,
 			    "invalid template");
 
 		for (p = template + tlen;
 		    p > template && *--p == 'X'; xc++);
 
 		if (xc < 3) /* the gnu mktemp errs on less than 3 */
-			err_no_cleanup(stfu, EINVAL,
+			err_exit(EINVAL,
 			"template must have 3 X or more on end (12+ advised");
 	}
 
@@ -116,31 +119,37 @@ main(int argc, char *argv[])
 	if (tmpdir != NULL) {
 		rp = realpath(tmpdir, resolved);
 		if (rp == NULL)
-			err_no_cleanup(stfu, errno, "%s", tmpdir);
+			err_exit(errno, "%s", tmpdir);
 
 		tmpdir = resolved;
 	}
 
 	if (new_tmp_common(&fd, &s, type,
 	    tmpdir, template) < 0)
-		err_no_cleanup(stfu, errno, "%s", s);
+		err_exit(errno, "%s", s);
 
 	xpledgex("stdio", NULL);
 
 	if (s == NULL)
-		err_no_cleanup(stfu, EFAULT, "bad string initialisation");
+		err_exit(EFAULT, "bad string initialisation");
 	if (*s == '\0')
-		err_no_cleanup(stfu, EFAULT, "empty string initialisation");
+		err_exit(EFAULT, "empty string initialisation");
 	if (slen(s, maxlen, &len) < 0)
-		err_no_cleanup(stfu, EFAULT, "unterminated string initialisiert");
+		err_exit(EFAULT, "unterminated string initialisiert");
 
 	printf("%s\n", s);
 
 	return EXIT_SUCCESS;
 
 err_usage:
-	err_no_cleanup(stfu, EINVAL,
+	err_exit(EINVAL,
 	    "usage: %s [-d] [-p dir] [template]\n", getnvmprogname());
+}
+
+static void
+exit_cleanup(void)
+{
+	return;
 }/* 
 
   ( >:3 )    
diff --git a/util/libreboot-utils/nvmutil.c b/util/libreboot-utils/nvmutil.c
index d78ab0c8..bab1945d 100644
--- a/util/libreboot-utils/nvmutil.c
+++ b/util/libreboot-utils/nvmutil.c
@@ -12,39 +12,44 @@
 #include <errno.h>
 #include <fcntl.h>
 #include <limits.h>
+#include <stdarg.h>
 #include <stddef.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
+#include <unistd.h>
 
 #include "include/common.h"
 
+static void
+exit_cleanup(void);
+
 int
 main(int argc, char *argv[])
 {
 	struct xstate *x;
-
 	struct commands *cmd;
 	struct xfile *f;
-
 	size_t c;
 
+	(void) errhook(exit_cleanup);
+
 	if (lbgetprogname(argv[0]) == NULL)
-		err_no_cleanup(0, errno, "could not set progname");
+		err_exit(errno, "could not set progname");
 
 	xpledgex("stdio flock rpath wpath cpath unveil", NULL);
 	xunveilx("/dev/urandom", "r");
 
 #ifndef S_ISREG
-	err_no_cleanup(0, ECANCELED,
+	err_exit(ECANCELED,
 	    "Can't determine file types (S_ISREG undefined)");
 #endif
 #if ((CHAR_BIT) != 8)
-	err_no_cleanup(0, ECANCELED, "Unsupported char size");
+	err_exit(ECANCELED, "Unsupported char size");
 #endif
 
 	if ((x = xstart(argc, argv)) == NULL)
-		err_no_cleanup(0, ECANCELED, "NULL state on init");
+		err_exit(ECANCELED, "NULL state on init");
 
 	/* parse user command */
 /* TODO: CHECK ACCESSES VIA xstatus() */
@@ -64,15 +69,12 @@ main(int argc, char *argv[])
 	xpledgex("stdio flock rpath wpath cpath", NULL);
 
 	if (cmd->run == NULL)
-		b0rk(errno, "Command not set");
+		err_exit(errno, "Command not set");
 
 	sanitize_command_list();
-
 	open_gbe_file();
-
 	copy_gbe();
 	read_checksums();
-
 	cmd->run();
 
 	for (c = 0; c < items(x->cmd); c++)
@@ -81,13 +83,17 @@ main(int argc, char *argv[])
 	if ((cmd->flags & O_ACCMODE) == O_RDWR)
 		write_to_gbe_bin();
 
-	if (exit_cleanup() == -1)
-		b0rk(EIO, "%s: close", f->fname);
-
+	exit_cleanup();
 	if (f->io_err_gbe_bin)
-		b0rk(EIO, "%s: error writing final file");
+		err_exit(EIO, "%s: error writing final file");
 
 	free_and_set_null(&f->tname);
 
 	return EXIT_SUCCESS;
 }
+
+static void
+exit_cleanup(void)
+{
+	return;
+}