*
* This applies patches on top of some (arbitrary) version of the SCM.
*
- * NOTE! It does all its work in the index file, and only cares about
- * the files in the working directory if you tell it to "merge" the
- * patch apply.
- *
- * Even when merging it always takes the source from the index, and
- * uses the working tree as a "branch" for a 3-way merge.
*/
-#include <ctype.h>
#include <fnmatch.h>
#include "cache.h"
+#include "quote.h"
-// We default to the merge behaviour, since that's what most people would
-// expect.
-//
// --check turns on checking that the working tree matches the
// files that are being modified, but doesn't apply the patch
// --stat does just a diffstat, and doesn't actually apply
-// --show-files shows the directory changes
+// --numstat does numeric diffstat, and doesn't actually apply
+// --index-info shows the old and new index info for paths if available.
//
-static int merge_patch = 1;
+static const char *prefix;
+static int prefix_length = -1;
+
+static int allow_binary_replacement = 0;
static int check_index = 0;
static int write_index = 0;
static int diffstat = 0;
+static int numstat = 0;
static int summary = 0;
static int check = 0;
static int apply = 1;
-static int show_files = 0;
+static int no_add = 0;
+static int show_index_info = 0;
+static int line_termination = '\n';
static const char apply_usage[] =
-"git-apply [--
no-merge] [--stat] [--summary] [--check] [--index] [--apply] [--show-files] <patch>...";
+"git-apply [--
stat] [--numstat] [--summary] [--check] [--index] [--apply] [--no-add] [--index-info] [--allow-binary-replacement] [-z] <patch>...";
/*
* For "diff-stat" like behaviour, we keep track of the biggest change
struct patch {
char *new_name, *old_name, *def_name;
unsigned int old_mode, new_mode;
- int is_rename, is_copy, is_new, is_delete;
+ int is_rename, is_copy, is_new, is_delete, is_binary;
int lines_added, lines_deleted;
int score;
struct fragment *fragments;
char *result;
unsigned long resultsize;
+ char old_sha1_prefix[41];
+ char new_sha1_prefix[41];
struct patch *next;
};
buffer = xrealloc(buffer, alloc);
nr = alloc - size;
}
- nr = read(fd, buffer + size, nr);
+ nr = xread(fd, buffer + size, nr);
if (!nr)
break;
- if (nr < 0) {
- if (errno == EAGAIN)
- continue;
+ if (nr < 0)
die("git-apply: read returned %s", strerror(errno));
- }
size += nr;
}
*sizep = size;
const char *start = line;
char *name;
+ if (*line == '"') {
+ /* Proposed "new-style" GNU patch/diff format; see
+ * http://marc.theaimsgroup.com/?l=git&m=112927316408690&w=2
+ */
+ name = unquote_c_style(line, NULL);
+ if (name) {
+ char *cp = name;
+ while (p_value) {
+ cp = strchr(name, '/');
+ if (!cp)
+ break;
+ cp++;
+ p_value--;
+ }
+ if (cp) {
+ /* name can later be freed, so we need
+ * to memmove, not just return cp
+ */
+ memmove(name, cp, strlen(cp) + 1);
+ free(def);
+ return name;
+ }
+ else {
+ free(name);
+ name = NULL;
+ }
+ }
+ }
+
for (;;) {
char c = *line;
*/
static char *gitdiff_verify_name(const char *line, int isnull, char *orig_name, const char *oldnew)
{
- int len;
- const char *name;
-
if (!orig_name && !isnull)
return find_name(line, NULL, 1, 0);
- name = "/dev/null";
- len = 9;
if (orig_name) {
+ int len;
+ const char *name;
+ char *another;
name = orig_name;
len = strlen(name);
if (isnull)
die("git-apply: bad git-diff - expected /dev/null, got %s on line %d", name, linenr);
- }
-
- if (*name == '/')
- goto absolute_path;
-
- for (;;) {
- char c = *line++;
- if (c == '\n')
- break;
- if (c != '/')
- continue;
-absolute_path:
- if (memcmp(line, name, len) || line[len] != '\n')
- break;
+ another = find_name(line, NULL, 1, 0);
+ if (!another || memcmp(another, name, len))
+ die("git-apply: bad git-diff - inconsistent %s filename on line %d", oldnew, linenr);
+ free(another);
return orig_name;
}
- die("git-apply: bad git-diff - inconsistent %s filename on line %d", oldnew, linenr);
- return NULL;
+ else {
+ /* expect "/dev/null" */
+ if (memcmp("/dev/null", line, 9) || line[9] != '\n')
+ die("git-apply: bad git-diff - expected /dev/null on line %d", linenr);
+ return NULL;
+ }
}
static int gitdiff_oldname(const char *line, struct patch *patch)
return 0;
}
+static int gitdiff_index(const char *line, struct patch *patch)
+{
+ /* index line is N hexadecimal, "..", N hexadecimal,
+ * and optional space with octal mode.
+ */
+ const char *ptr, *eol;
+ int len;
+
+ ptr = strchr(line, '.');
+ if (!ptr || ptr[1] != '.' || 40 < ptr - line)
+ return 0;
+ len = ptr - line;
+ memcpy(patch->old_sha1_prefix, line, len);
+ patch->old_sha1_prefix[len] = 0;
+
+ line = ptr + 2;
+ ptr = strchr(line, ' ');
+ eol = strchr(line, '\n');
+
+ if (!ptr || eol < ptr)
+ ptr = eol;
+ len = ptr - line;
+
+ if (40 < len)
+ return 0;
+ memcpy(patch->new_sha1_prefix, line, len);
+ patch->new_sha1_prefix[len] = 0;
+ if (*ptr == ' ')
+ patch->new_mode = patch->old_mode = strtoul(ptr+1, NULL, 8);
+ return 0;
+}
+
/*
* This is normal for a diff that doesn't change anything: we'll fall through
* into the next diff. Tell the parser to break out.
return -1;
}
-static char *git_header_name(char *line)
+static const char *stop_at_slash(const char *line, int llen)
+{
+ int i;
+
+ for (i = 0; i < llen; i++) {
+ int ch = line[i];
+ if (ch == '/')
+ return line + i;
+ }
+ return NULL;
+}
+
+/* This is to extract the same name that appears on "diff --git"
+ * line. We do not find and return anything if it is a rename
+ * patch, and it is OK because we will find the name elsewhere.
+ * We need to reliably find name only when it is mode-change only,
+ * creation or deletion of an empty file. In any of these cases,
+ * both sides are the same name under a/ and b/ respectively.
+ */
+static char *git_header_name(char *line, int llen)
{
int len;
- char *name, *second;
+ const char *name;
+ const char *second = NULL;
- /*
- * Find the first '/'
- */
- name = line;
- for (;;) {
- char c = *name++;
- if (c == '\n')
+ line += strlen("diff --git ");
+ llen -= strlen("diff --git ");
+
+ if (*line == '"') {
+ const char *cp;
+ char *first = unquote_c_style(line, &second);
+ if (!first)
return NULL;
- if (c == '/')
- break;
+
+ /* advance to the first slash */
+ cp = stop_at_slash(first, strlen(first));
+ if (!cp || cp == first) {
+ /* we do not accept absolute paths */
+ free_first_and_fail:
+ free(first);
+ return NULL;
+ }
+ len = strlen(cp+1);
+ memmove(first, cp+1, len+1); /* including NUL */
+
+ /* second points at one past closing dq of name.
+ * find the second name.
+ */
+ while ((second < line + llen) && isspace(*second))
+ second++;
+
+ if (line + llen <= second)
+ goto free_first_and_fail;
+ if (*second == '"') {
+ char *sp = unquote_c_style(second, NULL);
+ if (!sp)
+ goto free_first_and_fail;
+ cp = stop_at_slash(sp, strlen(sp));
+ if (!cp || cp == sp) {
+ free_both_and_fail:
+ free(sp);
+ goto free_first_and_fail;
+ }
+ /* They must match, otherwise ignore */
+ if (strcmp(cp+1, first))
+ goto free_both_and_fail;
+ free(sp);
+ return first;
+ }
+
+ /* unquoted second */
+ cp = stop_at_slash(second, line + llen - second);
+ if (!cp || cp == second)
+ goto free_first_and_fail;
+ cp++;
+ if (line + llen - cp != len + 1 ||
+ memcmp(first, cp, len))
+ goto free_first_and_fail;
+ return first;
}
- /*
- * We don't accept absolute paths (/dev/null) as possibly valid
- */
- if (name == line+1)
+ /* unquoted first name */
+ name = stop_at_slash(line, llen);
+ if (!name || name == line)
return NULL;
+ name++;
+
+ /* since the first name is unquoted, a dq if exists must be
+ * the beginning of the second name.
+ */
+ for (second = name; second < line + llen; second++) {
+ if (*second == '"') {
+ const char *cp = second;
+ const char *np;
+ char *sp = unquote_c_style(second, NULL);
+
+ if (!sp)
+ return NULL;
+ np = stop_at_slash(sp, strlen(sp));
+ if (!np || np == sp) {
+ free_second_and_fail:
+ free(sp);
+ return NULL;
+ }
+ np++;
+ len = strlen(np);
+ if (len < cp - name &&
+ !strncmp(np, name, len) &&
+ isspace(name[len])) {
+ /* Good */
+ memmove(sp, np, len + 1);
+ return sp;
+ }
+ goto free_second_and_fail;
+ }
+ }
+
/*
* Accept a name only if it shows up twice, exactly the same
* form.
default:
continue;
case '\n':
- break;
+ return NULL;
case '\t': case ' ':
second = name+len;
for (;;) {
* or removing or adding empty files), so we get
* the default name from the header.
*/
- patch->def_name = git_header_name(line + strlen("diff --git "));
+ patch->def_name = git_header_name(line, len);
line += len;
size -= len;
{ "rename to ", gitdiff_renamedst },
{ "similarity index ", gitdiff_similarity },
{ "dissimilarity index ", gitdiff_dissimilarity },
+ { "index ", gitdiff_index },
{ "", gitdiff_unrecognized },
};
int i;
struct fragment dummy;
if (parse_fragment_header(line, len, &dummy) < 0)
continue;
- error("patch fragment without header at line %d: %.*s", linenr, len-1, line);
+ error("patch fragment without header at line %d: %.*s", linenr, (int)len-1, line);
}
if (size < len + 6)
added++;
newlines--;
break;
- /* We allow "\ No newline at end of file" */
+
+ /* We allow "\ No newline at end of file". Depending
+ * on locale settings when the patch was produced we
+ * don't know what this line looks like. The only
+ * thing we do know is that it begins with "\ ".
+ * Checking for 12 is just for sanity check -- any
+ * l10n of "\ No newline..." is at least that long.
+ */
case '\\':
- if (len < 12 || memcmp(line, "\\ No newline", 12))
+ if (len < 12 || memcmp(line, "\\ ", 2))
return -1;
break;
}
* it in the above loop because we hit oldlines == newlines == 0
* before seeing it.
*/
- if (12 < size && !memcmp(line, "\\ No newline", 12))
+ if (12 < size && !memcmp(line, "\\ ", 2))
offset += linelen(line, size);
patch->lines_added += added;
return offset;
}
+static inline int metadata_changes(struct patch *patch)
+{
+ return patch->is_rename > 0 ||
+ patch->is_copy > 0 ||
+ patch->is_new > 0 ||
+ patch->is_delete ||
+ (patch->old_mode && patch->new_mode &&
+ patch->old_mode != patch->new_mode);
+}
+
static int parse_chunk(char *buffer, unsigned long size, struct patch *patch)
{
int hdrsize, patchsize;
patchsize = parse_single_patch(buffer + offset + hdrsize, size - offset - hdrsize, patch);
+ if (!patchsize) {
+ static const char *binhdr[] = {
+ "Binary files ",
+ "Files ",
+ NULL,
+ };
+ int i;
+ int hd = hdrsize + offset;
+ unsigned long llen = linelen(buffer + hd, size - hd);
+
+ if (!memcmp(" differ\n", buffer + hd + llen - 8, 8))
+ for (i = 0; binhdr[i]; i++) {
+ int len = strlen(binhdr[i]);
+ if (len < size - hd &&
+ !memcmp(binhdr[i], buffer + hd, len)) {
+ patch->is_binary = 1;
+ break;
+ }
+ }
+
+ /* Empty patch cannot be applied if:
+ * - it is a binary patch and we do not do binary_replace, or
+ * - text patch without metadata change
+ */
+ if ((apply || check) &&
+ (patch->is_binary
+ ? !allow_binary_replacement
+ : !metadata_changes(patch)))
+ die("patch with only garbage at line %d", linenr);
+ }
+
return offset + hdrsize + patchsize;
}
{
const char *prefix = "";
char *name = patch->new_name;
+ char *qname = NULL;
int len, max, add, del, total;
if (!name)
name = patch->old_name;
+ if (0 < (len = quote_c_style(name, NULL, NULL, 0))) {
+ qname = xmalloc(len + 1);
+ quote_c_style(name, qname, NULL, 0);
+ name = qname;
+ }
+
/*
* "scale" the filename
*/
add = (add * max + max_change / 2) / max_change;
del = total - add;
}
- printf(" %s%-*s |%5d %.*s%.*s\n", prefix,
- len, name, patch->lines_added + patch->lines_deleted,
- add, pluses, del, minuses);
+ if (patch->is_binary)
+ printf(" %s%-*s | Bin\n", prefix, len, name);
+ else
+ printf(" %s%-*s |%5d %.*s%.*s\n", prefix,
+ len, name, patch->lines_added + patch->lines_deleted,
+ add, pluses, del, minuses);
+ if (qname)
+ free(qname);
}
static int read_old_data(struct stat *st, const char *path, void *buf, unsigned long size)
return error("unable to open %s", path);
got = 0;
for (;;) {
- int ret = read(fd, buf + got, size - got);
- if (ret < 0) {
- if (errno == EAGAIN)
- continue;
- break;
- }
- if (!ret)
+ int ret = xread(fd, buf + got, size - got);
+ if (ret <= 0)
break;
got += ret;
}
break;
/* Fall-through for ' ' */
case '+':
- memcpy(new + newsize, patch + 1, plen);
- newsize += plen;
+ if (*patch != '+' || !no_add) {
+ memcpy(new + newsize, patch + 1, plen);
+ newsize += plen;
+ }
break;
case '@': case '\\':
/* Ignore it, we already handled it */
static int apply_fragments(struct buffer_desc *desc, struct patch *patch)
{
struct fragment *frag = patch->fragments;
+ const char *name = patch->old_name ? patch->old_name : patch->new_name;
+
+ if (patch->is_binary) {
+ unsigned char sha1[20];
+
+ if (!allow_binary_replacement)
+ return error("cannot apply binary patch to '%s' "
+ "without --allow-binary-replacement",
+ name);
+
+ /* For safety, we require patch index line to contain
+ * full 40-byte textual SHA1 for old and new, at least for now.
+ */
+ if (strlen(patch->old_sha1_prefix) != 40 ||
+ strlen(patch->new_sha1_prefix) != 40 ||
+ get_sha1_hex(patch->old_sha1_prefix, sha1) ||
+ get_sha1_hex(patch->new_sha1_prefix, sha1))
+ return error("cannot apply binary patch to '%s' "
+ "without full index line", name);
+
+ if (patch->old_name) {
+ unsigned char hdr[50];
+ int hdrlen;
+
+ /* See if the old one matches what the patch
+ * applies to.
+ */
+ write_sha1_file_prepare(desc->buffer, desc->size,
+ "blob", sha1, hdr, &hdrlen);
+ if (strcmp(sha1_to_hex(sha1), patch->old_sha1_prefix))
+ return error("the patch applies to '%s' (%s), "
+ "which does not match the "
+ "current contents.",
+ name, sha1_to_hex(sha1));
+ }
+ else {
+ /* Otherwise, the old one must be empty. */
+ if (desc->size)
+ return error("the patch applies to an empty "
+ "'%s' but it is not empty", name);
+ }
+
+ /* For now, we do not record post-image data in the patch,
+ * and require the object already present in the recipient's
+ * object database.
+ */
+ if (desc->buffer) {
+ free(desc->buffer);
+ desc->alloc = desc->size = 0;
+ }
+ get_sha1_hex(patch->new_sha1_prefix, sha1);
+
+ if (memcmp(sha1, null_sha1, 20)) {
+ char type[10];
+ unsigned long size;
+
+ desc->buffer = read_sha1_file(sha1, type, &size);
+ if (!desc->buffer)
+ return error("the necessary postimage %s for "
+ "'%s' does not exist",
+ patch->new_sha1_prefix, name);
+ desc->alloc = desc->size = size;
+ }
+
+ return 0;
+ }
while (frag) {
if (apply_one_fragment(desc, frag) < 0)
- return error("patch failed: %s:%d", patch->old_name, frag->oldpos);
+ return error("patch failed: %s:%ld",
+ name, frag->oldpos);
frag = frag->next;
}
return 0;
struct stat st;
const char *old_name = patch->old_name;
const char *new_name = patch->new_name;
+ const char *name = old_name ? old_name : new_name;
if (old_name) {
int changed;
+ int stat_ret = lstat(old_name, &st);
- if (lstat(old_name, &st) < 0)
- return error("%s: %s", old_name, strerror(errno));
if (check_index) {
int pos = cache_name_pos(old_name, strlen(old_name));
if (pos < 0)
- return error("%s: does not exist in index", old_name);
+ return error("%s: does not exist in index",
+ old_name);
+ if (stat_ret < 0) {
+ struct checkout costate;
+ if (errno != ENOENT)
+ return error("%s: %s", old_name,
+ strerror(errno));
+ /* checkout */
+ costate.base_dir = "";
+ costate.base_dir_len = 0;
+ costate.force = 0;
+ costate.quiet = 0;
+ costate.not_new = 0;
+ costate.refresh_cache = 1;
+ if (checkout_entry(active_cache[pos],
+ &costate) ||
+ lstat(old_name, &st))
+ return -1;
+ }
+
changed = ce_match_stat(active_cache[pos], &st);
if (changed)
- return error("%s: does not match index", old_name);
+ return error("%s: does not match index",
+ old_name);
}
+ else if (stat_ret < 0)
+ return error("%s: %s", old_name, strerror(errno));
+
if (patch->is_new < 0)
patch->is_new = 0;
st.st_mode = ntohl(create_ce_mode(st.st_mode));
return error("%s: already exists in working directory", new_name);
if (errno != ENOENT)
return error("%s: %s", new_name, strerror(errno));
- if (!patch->new_mode)
- patch->new_mode = S_IFREG | 0644;
+ if (!patch->new_mode) {
+ if (patch->is_new)
+ patch->new_mode = S_IFREG | 0644;
+ else
+ patch->new_mode = patch->old_mode;
+ }
}
if (new_name && old_name) {
}
if (apply_data(patch, &st) < 0)
- return error("%s: patch does not apply", old_name);
+ return error("%s: patch does not apply", name);
return 0;
}
return error;
}
-static void show_file(int c, unsigned int mode, const char *name)
+static inline int is_null_sha1(const unsigned char *sha1)
{
- printf("%c %o %s\n", c, mode, name);
+ return !memcmp(sha1, null_sha1, 20);
}
-static void show_file_list(struct patch *patch)
+static void show_index_list(struct patch *list)
{
- for (;patch ; patch = patch->next) {
- if (patch->is_rename) {
- show_file('-', patch->old_mode, patch->old_name);
- show_file('+', patch->new_mode, patch->new_name);
- continue;
- }
- if (patch->is_copy || patch->is_new) {
- show_file('+', patch->new_mode, patch->new_name);
- continue;
- }
- if (patch->is_delete) {
- show_file('-', patch->old_mode, patch->old_name);
- continue;
- }
- if (patch->old_mode && patch->new_mode && patch->old_mode != patch->new_mode) {
- printf("M %o:%o %s\n", patch->old_mode, patch->new_mode, patch->old_name);
- continue;
- }
- printf("M %o %s\n", patch->old_mode, patch->old_name);
+ struct patch *patch;
+
+ /* Once we start supporting the reverse patch, it may be
+ * worth showing the new sha1 prefix, but until then...
+ */
+ for (patch = list; patch; patch = patch->next) {
+ const unsigned char *sha1_ptr;
+ unsigned char sha1[20];
+ const char *name;
+
+ name = patch->old_name ? patch->old_name : patch->new_name;
+ if (patch->is_new)
+ sha1_ptr = null_sha1;
+ else if (get_sha1(patch->old_sha1_prefix, sha1))
+ die("sha1 information is lacking or useless (%s).",
+ name);
+ else
+ sha1_ptr = sha1;
+
+ printf("%06o %s ",patch->old_mode, sha1_to_hex(sha1_ptr));
+ if (line_termination && quote_c_style(name, NULL, NULL, 0))
+ quote_c_style(name, NULL, stdout, 0);
+ else
+ fputs(name, stdout);
+ putchar(line_termination);
}
}
printf(" %d files changed, %d insertions(+), %d deletions(-)\n", files, adds, dels);
}
+static void numstat_patch_list(struct patch *patch)
+{
+ for ( ; patch; patch = patch->next) {
+ const char *name;
+ name = patch->old_name ? patch->old_name : patch->new_name;
+ printf("%d\t%d\t", patch->lines_added, patch->lines_deleted);
+ if (line_termination && quote_c_style(name, NULL, NULL, 0))
+ quote_c_style(name, NULL, stdout, 0);
+ else
+ fputs(name, stdout);
+ putchar('\n');
+ }
+}
+
static void show_file_mode_name(const char *newdelete, unsigned int mode, const char *name)
{
if (mode)
if (lines > max_change)
max_change = lines;
if (patch->old_name) {
- int len = strlen(patch->old_name);
+ int len = quote_c_style(patch->old_name, NULL, NULL, 0);
+ if (!len)
+ len = strlen(patch->old_name);
if (len > max_len)
max_len = len;
}
if (patch->new_name) {
- int len = strlen(patch->new_name);
+ int len = quote_c_style(patch->new_name, NULL, NULL, 0);
+ if (!len)
+ len = strlen(patch->new_name);
if (len > max_len)
max_len = len;
}
if (S_ISLNK(mode))
return symlink(buf, path);
- fd = open(path, O_CREAT | O_EXCL | O_WRONLY | O_TRUNC, (mode & 0100) ? 0777 : 0666);
+ fd = open(path, O_CREAT | O_EXCL | O_WRONLY, (mode & 0100) ? 0777 : 0666);
if (fd < 0)
return -1;
while (size) {
- int written = write(fd, buf, size);
- if (written < 0) {
- if (errno == EINTR || errno == EAGAIN)
- continue;
+ int written = xwrite(fd, buf, size);
+ if (written < 0)
die("writing file %s: %s", path, strerror(errno));
- }
if (!written)
die("out of space writing file %s", path);
buf += written;
}
if (errno != EEXIST)
break;
- }
+ ++nr;
+ }
}
die("unable to write file %s mode %o", path, mode);
}
static int use_patch(struct patch *p)
{
- const char *pathname = p->new_name ? : p->old_name;
+ const char *pathname = p->new_name ? p->new_name : p->old_name;
struct excludes *x = excludes;
while (x) {
if (fnmatch(x->path, pathname, 0) == 0)
return 0;
x = x->next;
}
+ if (0 < prefix_length) {
+ int pathlen = strlen(pathname);
+ if (pathlen <= prefix_length ||
+ memcmp(prefix, pathname, prefix_length))
+ return 0;
+ }
return 1;
}
die("Unable to write new cachefile");
}
- if (show_files)
- show_file_list(list);
+ if (show_index_info)
+ show_index_list(list);
if (diffstat)
stat_patch_list(list);
+ if (numstat)
+ numstat_patch_list(list);
+
if (summary)
summary_patch_list(list);
excludes = x;
continue;
}
- /* NEEDSWORK: this does not do anything at this moment. */
- if (!strcmp(arg, "--no-merge")) {
- merge_patch = 0;
+ if (!strcmp(arg, "--no-add")) {
+ no_add = 1;
continue;
}
if (!strcmp(arg, "--stat")) {
diffstat = 1;
continue;
}
+ if (!strcmp(arg, "--allow-binary-replacement")) {
+ allow_binary_replacement = 1;
+ continue;
+ }
+ if (!strcmp(arg, "--numstat")) {
+ apply = 0;
+ numstat = 1;
+ continue;
+ }
if (!strcmp(arg, "--summary")) {
apply = 0;
summary = 1;
apply = 1;
continue;
}
- if (!strcmp(arg, "--show-files")) {
- show_files = 1;
+ if (!strcmp(arg, "--index-info")) {
+ apply = 0;
+ show_index_info = 1;
continue;
}
+ if (!strcmp(arg, "-z")) {
+ line_termination = 0;
+ continue;
+ }
+
+ if (check_index && prefix_length < 0) {
+ prefix = setup_git_directory();
+ prefix_length = prefix ? strlen(prefix) : 0;
+ git_config(git_default_config);
+ }
+ if (0 < prefix_length)
+ arg = prefix_filename(prefix, prefix_length, arg);
+
fd = open(arg, O_RDONLY);
if (fd < 0)
usage(apply_usage);