diff --git a/include/util/input_file.h b/include/util/input_file.h
index 3b762b4..03fff24 100644
--- a/include/util/input_file.h
+++ b/include/util/input_file.h
@@ -1,23 +1,18 @@
 #ifndef INPUT_FILE_H
 #define INPUT_FILE_H
 
-#include <stdio.h>
-
-typedef struct {
-	FILE *f;
-	char *line;
-	const char *filename;
-	size_t linenum;
-} input_file_t;
+#include <stddef.h>
 
 typedef struct {
 	const char *name;
-	int (*handle)(input_file_t *f, void *obj);
+	int (*handle)(char *line, const char *filename,
+		      size_t linenum, void *obj);
 } keyword_handler_t;
 
 int process_file(const char *filename, const keyword_handler_t *handlers,
 		 size_t count, void *obj);
 
-void input_file_complain(const input_file_t *f, const char *msg);
+void input_file_complain(const char *filename, size_t linenum,
+			 const char *msg);
 
 #endif /* INPUT_FILE_H */
diff --git a/lib/util/input_file.c b/lib/util/input_file.c
index b89565f..3954266 100644
--- a/lib/util/input_file.c
+++ b/lib/util/input_file.c
@@ -1,122 +1,58 @@
-#include <stdlib.h>
 #include <string.h>
-#include <errno.h>
+#include <stdio.h>
 #include <ctype.h>
 
 #include "util/input_file.h"
+#include "util/util.h"
 
-static int prefetch_line(input_file_t *f)
+void input_file_complain(const char *filename, size_t linenum, const char *msg)
 {
-	char *line, *ptr;
-	ssize_t ret;
-	size_t n;
-retry:
-	free(f->line);
-	f->line = NULL;
-
-	errno = 0;
-	line = NULL;
-	n = 0;
-	ret = getline(&line, &n, f->f);
-
-	if (ret < 0) {
-		if (errno != 0) {
-			perror(f->filename);
-			free(line);
-			return -1;
-		}
-		free(line);
-		return 1;
-	}
-
-	n = strlen(line);
-	while (n >0 && isspace(line[n - 1]))
-		--n;
-	line[n] = '\0';
-
-	f->line = line;
-	f->linenum += 1;
-
-	for (ptr = f->line; isspace(*ptr); ++ptr)
-		;
-
-	if (*ptr == '\0' || *ptr == '#')
-		goto retry;
-
-	if (ptr != f->line)
-		memmove(f->line, ptr, strlen(ptr) + 1);
-
-	ptr = f->line + strlen(f->line);
-
-	while (ptr > f->line && isspace(ptr[-1]))
-		--ptr;
-	*ptr = '\0';
-
-	if (f->line[0] == '\0')
-		goto retry;
-	return 0;
+	fprintf(stderr, "%s: %zu: %s\n", filename, linenum, msg);
 }
 
-void input_file_complain(const input_file_t *f, const char *msg)
+struct userdata {
+	const keyword_handler_t *handlers;
+	size_t count;
+	void *obj;
+};
+
+static int handle_line(void *usr, const char *filename,
+		       size_t linenum, char *line)
 {
-	fprintf(stderr, "%s: %zu: %s\n", f->filename, f->linenum, msg);
+	struct userdata *u = usr;
+	size_t i, len;
+
+	while (isspace(*line))
+		++line;
+
+	if (*line == '\0' || *line == '#')
+		return 0;
+
+	for (i = 0; i < u->count; ++i) {
+		len = strlen(u->handlers[i].name);
+
+		if (strncmp(line, u->handlers[i].name, len) != 0)
+			continue;
+		if (!isspace(line[len]) && line[len] != '\0')
+			continue;
+		for (line += len; isspace(*line); ++line)
+			;
+		break;
+	}
+
+	if (i == u->count) {
+		fprintf(stderr, "%s: %zu: unknown keyword\n",
+			filename, linenum);
+		return -1;
+	}
+
+	return u->handlers[i].handle(line, filename, linenum, u->obj);
 }
 
 int process_file(const char *filename, const keyword_handler_t *handlers,
 		 size_t count, void *obj)
 {
-	input_file_t f;
-	size_t i, len;
-	char *ptr;
-	int ret;
+	struct userdata u = { handlers, count, obj };
 
-	memset(&f, 0, sizeof(f));
-
-	f.filename = filename;
-	f.f = fopen(filename, "r");
-
-	if (f.f == NULL) {
-		perror(f.filename);
-		return -1;
-	}
-
-	for (;;) {
-		ret = prefetch_line(&f);
-		if (ret < 0)
-			goto fail;
-		if (ret > 0)
-			break;
-
-		ptr = f.line;
-
-		for (i = 0; i < count; ++i) {
-			len = strlen(handlers[i].name);
-
-			if (strncmp(ptr, handlers[i].name, len) != 0)
-				continue;
-			if (!isspace(ptr[len]) && ptr[len] != '\0')
-				continue;
-			for (ptr += len; isspace(*ptr); ++ptr)
-				;
-			memmove(f.line, ptr, strlen(ptr) + 1);
-			break;
-		}
-
-		if (i == count) {
-			fprintf(stderr, "%s: %zu: unknown keyword\n",
-				f.filename, f.linenum);
-			goto fail;
-		}
-
-		if (handlers[i].handle(&f, obj))
-			goto fail;
-	}
-
-	fclose(f.f);
-	free(f.line);
-	return 0;
-fail:
-	fclose(f.f);
-	free(f.line);
-	return -1;
+	return foreach_line_in_file(filename, &u, handle_line);
 }
diff --git a/main/cmd/buildstrategy/buildstrategy.c b/main/cmd/buildstrategy/buildstrategy.c
index 57e0a4f..936ce28 100644
--- a/main/cmd/buildstrategy/buildstrategy.c
+++ b/main/cmd/buildstrategy/buildstrategy.c
@@ -1,65 +1,37 @@
 #include "buildstrategy.h"
 
-typedef int (*line_handler_t)(const char *lhs, const char *rhs);
+typedef int (*line_handler_t)(const char *filename, size_t linenum,
+			      const char *lhs, const char *rhs);
+
+struct userdata {
+	line_handler_t cb;
+};
+
+static int handle_line(void *usr, const char *filename,
+		       size_t linenum, char *line)
+{
+	struct userdata *u = usr;
+	char *rhs;
+
+	rhs = strchr(line, ',');
+	if (rhs == NULL)
+		return 0;
+
+	*(rhs++) = '\0';
+	while (isspace(*rhs))
+		++rhs;
+
+	if (*line == '\0' || *rhs == '\0')
+		return 0;
+
+	return u->cb(filename, linenum, line, rhs);
+}
 
 static int foreach_line(const char *filename, line_handler_t cb)
 {
-	FILE *f = fopen(filename, "r");
+	struct userdata u = { cb };
 
-	for (;;) {
-		char *line = NULL, *rhs, *lhs, *ptr;
-		size_t n = 0;
-		ssize_t ret;
-
-		errno = 0;
-		ret = getline(&line, &n, f);
-
-		if (ret < 0) {
-			if (errno == 0) {
-				free(line);
-				break;
-			}
-			perror(filename);
-			free(line);
-			fclose(f);
-			return -1;
-		}
-
-		rhs = strchr(line, ',');
-		if (rhs == NULL) {
-			free(line);
-			continue;
-		}
-
-		*(rhs++) = '\0';
-		while (isspace(*rhs))
-			++rhs;
-
-		ptr = rhs;
-		while (*ptr != '\0' && !isspace(*ptr))
-			++ptr;
-		*ptr = '\0';
-
-		lhs = line;
-		while (isspace(*lhs))
-			++lhs;
-
-		if (*lhs == '\0' || *rhs == '\0') {
-			free(line);
-			continue;
-		}
-
-		if (cb(lhs, rhs)) {
-			free(line);
-			fclose(f);
-			return -1;
-		}
-
-		free(line);
-	}
-
-	fclose(f);
-	return 0;
+	return foreach_line_in_file(filename, &u, handle_line);
 }
 
 /*****************************************************************************/
@@ -67,7 +39,8 @@ static int foreach_line(const char *filename, line_handler_t cb)
 static hash_table_t tbl_provides;
 static hash_table_t tbl_sourcepkgs;
 
-static int handle_depends(const char *sourcepkg, const char *binpkg)
+static int handle_depends(const char *filename, size_t linenum,
+			  const char *sourcepkg, const char *binpkg)
 {
 	source_pkg_t *src, *dep;
 	size_t count;
@@ -79,8 +52,9 @@ static int handle_depends(const char *sourcepkg, const char *binpkg)
 
 	dep = hash_table_lookup(&tbl_provides, binpkg);
 	if (dep == NULL) {
-		fprintf(stderr, "nothing provides '%s' required by '%s'\n",
-			binpkg, sourcepkg);
+		fprintf(stderr,
+			"%s: %zu: nothing provides '%s' required by '%s'\n",
+			filename, linenum, binpkg, sourcepkg);
 		return -1;
 	}
 
@@ -100,14 +74,16 @@ static int handle_depends(const char *sourcepkg, const char *binpkg)
 	return 0;
 }
 
-static int handle_provides(const char *sourcepkg, const char *binpkg)
+static int handle_provides(const char *filename, size_t linenum,
+			   const char *sourcepkg, const char *binpkg)
 {
 	source_pkg_t *src = NULL;
 
 	src = hash_table_lookup(&tbl_provides, binpkg);
 	if (src != NULL) {
-		fprintf(stderr, "%s: package already provided by %s\n",
-			binpkg, src->name);
+		fprintf(stderr,
+			"%s: %zu: %s: package already provided by %s\n",
+			filename, linenum, binpkg, src->name);
 		return -1;
 	}
 
diff --git a/main/cmd/buildstrategy/buildstrategy.h b/main/cmd/buildstrategy/buildstrategy.h
index 56ad229..4293ade 100644
--- a/main/cmd/buildstrategy/buildstrategy.h
+++ b/main/cmd/buildstrategy/buildstrategy.h
@@ -9,6 +9,7 @@
 #include <errno.h>
 
 #include "command.h"
+#include "util/util.h"
 #include "util/hashtable.h"
 
 enum {
diff --git a/main/cmd/pack/desc.c b/main/cmd/pack/desc.c
index bde1a66..d7d2969 100644
--- a/main/cmd/pack/desc.c
+++ b/main/cmd/pack/desc.c
@@ -1,8 +1,9 @@
 #include "pack.h"
 
-static int handle_requires(input_file_t *f, void *obj)
+static int handle_requires(char *line, const char *filename,
+			   size_t linenum, void *obj)
 {
-	char *ptr = f->line, *end;
+	char *ptr = line, *end;
 	pkg_desc_t *desc = obj;
 	dependency_t *dep;
 	size_t len;
@@ -19,13 +20,14 @@ static int handle_requires(input_file_t *f, void *obj)
 			break;
 
 		if (len > 0xFF) {
-			input_file_complain(f, "dependency name too long");
+			input_file_complain(filename, linenum, "dependency name too long");
 			return -1;
 		}
 
 		dep = calloc(1, sizeof(*dep) + len + 1);
 		if (dep == NULL) {
-			input_file_complain(f, "out of memory");
+			input_file_complain(filename, linenum,
+					    "out of memory");
 			return -1;
 		}
 
@@ -40,28 +42,30 @@ static int handle_requires(input_file_t *f, void *obj)
 	return 0;
 }
 
-static int handle_toc_compressor(input_file_t *f, void *obj)
+static int handle_toc_compressor(char *line, const char *filename,
+				 size_t linenum, void *obj)
 {
 	pkg_desc_t *desc = obj;
 
-	desc->toccmp = compressor_by_name(f->line);
+	desc->toccmp = compressor_by_name(line);
 
 	if (desc->toccmp == NULL) {
-		input_file_complain(f, "unkown compressor");
+		input_file_complain(filename, linenum, "unkown compressor");
 		return -1;
 	}
 
 	return 0;
 }
 
-static int handle_data_compressor(input_file_t *f, void *obj)
+static int handle_data_compressor(char *line, const char *filename,
+				  size_t linenum, void *obj)
 {
 	pkg_desc_t *desc = obj;
 
-	desc->datacmp = compressor_by_name(f->line);
+	desc->datacmp = compressor_by_name(line);
 
 	if (desc->datacmp == NULL) {
-		input_file_complain(f, "unkown compressor");
+		input_file_complain(filename, linenum, "unkown compressor");
 		return -1;
 	}
 
diff --git a/main/cmd/pack/filelist.c b/main/cmd/pack/filelist.c
index 24f8952..3de5f92 100644
--- a/main/cmd/pack/filelist.c
+++ b/main/cmd/pack/filelist.c
@@ -7,20 +7,20 @@ static char *skipspace(char *str)
 	return str;
 }
 
-static void oom(input_file_t *f)
+static void oom(const char *filename, size_t linenum)
 {
-	input_file_complain(f, "out of memory");
+	input_file_complain(filename, linenum, "out of memory");
 }
 
-static image_entry_t *filelist_mkentry(input_file_t *f, mode_t filetype)
+static image_entry_t *filelist_mkentry(char *line, const char *filename,
+				       size_t linenum, mode_t filetype)
 {
-	char *line = f->line;
 	image_entry_t *ent;
 	size_t i;
 
 	ent = calloc(1, sizeof(*ent));
 	if (ent == NULL) {
-		oom(f);
+		oom(filename, linenum);
 		return NULL;
 	}
 
@@ -29,29 +29,31 @@ static image_entry_t *filelist_mkentry(input_file_t *f, mode_t filetype)
 		;
 
 	if (!isspace(line[i])) {
-		input_file_complain(f, "expected space after file name");
+		input_file_complain(filename, linenum,
+				    "expected space after file name");
 		goto fail;
 	}
 
 	ent->name = calloc(1, i + 1);
 	if (ent->name == NULL) {
-		oom(f);
+		oom(filename, linenum);
 		goto fail;
 	}
 
 	memcpy(ent->name, line, i);
 	if (canonicalize_name(ent->name)) {
-		input_file_complain(f, "invalid file name");
+		input_file_complain(filename, linenum, "invalid file name");
 		goto fail;
 	}
 
 	if (ent->name[0] == '\0') {
-		input_file_complain(f, "refusing to add entry for '/'");
+		input_file_complain(filename, linenum,
+				    "refusing to add entry for '/'");
 		goto fail;
 	}
 
 	if (strlen(ent->name) > 0xFFFF) {
-		input_file_complain(f, "name too long");
+		input_file_complain(filename, linenum, "name too long");
 		goto fail;
 	}
 
@@ -59,20 +61,23 @@ static image_entry_t *filelist_mkentry(input_file_t *f, mode_t filetype)
 
 	/* mode */
 	if (!isdigit(*line)) {
-		input_file_complain(f, "expected numeric mode after file name");
+		input_file_complain(filename, linenum,
+				    "expected numeric mode after file name");
 		goto fail;
 	}
 
 	while (isdigit(*line)) {
 		if (*line > '7') {
-			input_file_complain(f, "mode must be octal number");
+			input_file_complain(filename, linenum,
+					    "mode must be octal number");
 			goto fail;
 		}
 		ent->mode = (ent->mode << 3) | (*(line++) - '0');
 	}
 
 	if (!isspace(*line)) {
-		input_file_complain(f, "expected space after file mode");
+		input_file_complain(filename, linenum,
+				    "expected space after file mode");
 		goto fail;
 	}
 
@@ -82,7 +87,8 @@ static image_entry_t *filelist_mkentry(input_file_t *f, mode_t filetype)
 
 	/* uid */
 	if (!isdigit(*line)) {
-		input_file_complain(f, "expected numeric UID after mode");
+		input_file_complain(filename, linenum,
+				    "expected numeric UID after mode");
 		goto fail;
 	}
 
@@ -90,7 +96,8 @@ static image_entry_t *filelist_mkentry(input_file_t *f, mode_t filetype)
 		ent->uid = (ent->uid * 10) + (*(line++) - '0');
 
 	if (!isspace(*line)) {
-		input_file_complain(f, "expected space after UID");
+		input_file_complain(filename, linenum,
+				    "expected space after UID");
 		goto fail;
 	}
 
@@ -98,7 +105,8 @@ static image_entry_t *filelist_mkentry(input_file_t *f, mode_t filetype)
 
 	/* gid */
 	if (!isdigit(*line)) {
-		input_file_complain(f, "expected numeric GID after UID");
+		input_file_complain(filename, linenum,
+				    "expected numeric GID after UID");
 		goto fail;
 	}
 
@@ -108,7 +116,7 @@ static image_entry_t *filelist_mkentry(input_file_t *f, mode_t filetype)
 	line = skipspace(line);
 
 	/* remove processed data */
-	memmove(f->line, line, strlen(line) + 1);
+	memmove(line, line, strlen(line) + 1);
 	return ent;
 fail:
 	free(ent->name);
@@ -116,9 +124,10 @@ fail:
 	return NULL;
 }
 
-int filelist_mkdir(input_file_t *f, void *obj)
+int filelist_mkdir(char *line, const char *filename,
+		   size_t linenum, void *obj)
 {
-	image_entry_t *ent = filelist_mkentry(f, S_IFDIR);
+	image_entry_t *ent = filelist_mkentry(line,filename,linenum,S_IFDIR);
 	image_entry_t **listptr = obj;
 
 	if (ent == NULL)
@@ -129,22 +138,24 @@ int filelist_mkdir(input_file_t *f, void *obj)
 	return 0;
 }
 
-int filelist_mkslink(input_file_t *f, void *obj)
+int filelist_mkslink(char *line, const char *filename,
+		     size_t linenum, void *obj)
 {
-	image_entry_t *ent = filelist_mkentry(f, S_IFLNK);
+	image_entry_t *ent = filelist_mkentry(line,filename,linenum,S_IFLNK);
 	image_entry_t **listptr = obj;
 
 	if (ent == NULL)
 		return -1;
 
-	ent->data.symlink.target = strdup(f->line);
+	ent->data.symlink.target = strdup(line);
 	if (ent->data.symlink.target == NULL) {
-		oom(f);
+		oom(filename, linenum);
 		goto fail;
 	}
 
 	if (strlen(ent->data.symlink.target) > 0xFFFF) {
-		input_file_complain(f, "symlink target too long");
+		input_file_complain(filename, linenum,
+				    "symlink target too long");
 		goto fail;
 	}
 
@@ -156,9 +167,10 @@ fail:
 	return -1;
 }
 
-int filelist_mkfile(input_file_t *f, void *obj)
+int filelist_mkfile(char *line, const char *filename,
+		    size_t linenum, void *obj)
 {
-	image_entry_t *ent = filelist_mkentry(f, S_IFREG);
+	image_entry_t *ent = filelist_mkentry(line,filename,linenum,S_IFREG);
 	image_entry_t **listptr = obj;
 	const char *ptr;
 	struct stat sb;
@@ -166,22 +178,22 @@ int filelist_mkfile(input_file_t *f, void *obj)
 	if (ent == NULL)
 		return -1;
 
-	if (f->line[0] == '\0') {
-		ptr = strrchr(f->filename, '/');
+	if (line[0] == '\0') {
+		ptr = strrchr(filename, '/');
 
 		if (ptr == NULL) {
 			ent->data.file.location = strdup(ent->name);
 		} else {
 			asprintf(&ent->data.file.location, "%.*s/%s",
-				 (int)(ptr - f->filename), f->filename,
+				 (int)(ptr - filename), filename,
 				 ent->name);
 		}
 	} else {
-		ent->data.file.location = strdup(f->line);
+		ent->data.file.location = strdup(line);
 	}
 
 	if (ent->data.file.location == NULL) {
-		oom(f);
+		oom(filename, linenum);
 		goto fail;
 	}
 
@@ -192,7 +204,8 @@ int filelist_mkfile(input_file_t *f, void *obj)
 
 	if (sizeof(off_t) > sizeof(uint64_t) &&
 	    sb.st_size > (off_t)(~((uint64_t)0))) {
-		input_file_complain(f, "input file is too big");
+		input_file_complain(filename, linenum,
+				    "input file is too big");
 		goto fail;
 	}
 
@@ -206,17 +219,18 @@ fail:
 	return -1;
 }
 
-static int filelist_mknod(input_file_t *f, void *obj)
+static int filelist_mknod(char *line, const char *filename,
+			  size_t linenum, void *obj)
 {
 	image_entry_t **listptr = obj, *ent;
 	unsigned int maj, min;
 	char *ptr;
 
-	ent = filelist_mkentry(f, S_IFCHR);
+	ent = filelist_mkentry(line, filename, linenum, S_IFCHR);
 	if (ent == NULL)
 		return -1;
 
-	switch (f->line[0]) {
+	switch (line[0]) {
 	case 'c':
 	case 'C':
 		break;
@@ -228,10 +242,10 @@ static int filelist_mknod(input_file_t *f, void *obj)
 		goto fail;
 	}
 
-	if (!isspace(f->line[1]))
+	if (!isspace(line[1]))
 		goto fail;
 
-	ptr = f->line + 1;
+	ptr = line + 1;
 	while (isspace(*ptr))
 		++ptr;
 
@@ -245,7 +259,8 @@ static int filelist_mknod(input_file_t *f, void *obj)
 	return 0;
 fail:
 	image_entry_free(ent);
-	input_file_complain(f, "error in device specification");
+	input_file_complain(filename, linenum,
+			    "error in device specification");
 	return -1;
 }
 
diff --git a/main/cmd/pack/pack.h b/main/cmd/pack/pack.h
index ace3407..eece7f1 100644
--- a/main/cmd/pack/pack.h
+++ b/main/cmd/pack/pack.h
@@ -38,11 +38,14 @@ typedef struct {
 	char *name;
 } pkg_desc_t;
 
-int filelist_mkdir(input_file_t *f, void *obj);
+int filelist_mkdir(char *line, const char *filename,
+		   size_t linenum, void *obj);
 
-int filelist_mkslink(input_file_t *f, void *obj);
+int filelist_mkslink(char *line, const char *filename,
+		     size_t linenum, void *obj);
 
-int filelist_mkfile(input_file_t *f, void *obj);
+int filelist_mkfile(char *line, const char *filename,
+		    size_t linenum, void *obj);
 
 int filelist_read(const char *filename, image_entry_t **out);