On 04/01/2015 01:32 PM, Jody Bruchon wrote:
On 4/1/2015 7:22 AM, Nils Stec wrote:
+ * Returns -1 if OPT_NOCLOBBER is set and a file is skipped if existent.
...
+ } else if (ISFLAG(OPT_NOCLOBBER)) {
+ return -1;
...
+ retval = copyfile(srcname, destname, 0);
+ if (!retval) goto error_copy;
This causes an error to be returned if someone asks for no clobbering.
Doing what is asked for by the user should never be an error condition
and should return success unless a true error occurred (i.e. write
errors). Here's example output when using the -n switch with GNU
coreutils 'cp' and testing for any error conditions:
$ ls -l foo bar
bar:
total 0
-rw-r--r-- 1 user user 0 Apr 1 07:31 1
-rw-r--r-- 1 user user 0 Apr 1 07:31 2
foo:
total 12
-rw-r--r-- 1 user user 4 Apr 1 07:31 1
-rw-r--r-- 1 user user 4 Apr 1 07:31 2
-rw-r--r-- 1 user user 4 Apr 1 07:31 3
$ cp -n foo/* bar/ || echo error
$ cp -n foo/* bar/ && echo success
success
$ ls -l foo bar
bar:
total 4
-rw-r--r-- 1 user user 0 Apr 1 07:31 1
-rw-r--r-- 1 user user 0 Apr 1 07:31 2
-rw-r--r-- 1 user user 4 Apr 1 07:32 3
foo:
total 12
-rw-r--r-- 1 user user 4 Apr 1 07:31 1
-rw-r--r-- 1 user user 4 Apr 1 07:31 2
-rw-r--r-- 1 user user 4 Apr 1 07:31 3
$
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diff --git a/elkscmd/file_utils/cp.c b/elkscmd/file_utils/cp.c
index 6e23864..2e413e9 100644
--- a/elkscmd/file_utils/cp.c
+++ b/elkscmd/file_utils/cp.c
@@ -20,11 +20,25 @@
#include <grp.h>
#include <utime.h>
#include <errno.h>
+#include <stdint.h>
#define BUF_SIZE 4096
static char *buf;
+/* macros for flag setting/clearing/testing */
+#define ISFLAG(a) ((flags & a) == a)
+#define SETFLAG(a) (flags |= a)
+#define CLRFLAG(a) (flags &= ~(a))
+
+/* some flags for command-line-options */
+static uint16_t flags;
+#define OPT_NOCLOBBER 0x0001
+#define OPT_VERBOSE 0x0002
+#define OPT_INTERACTIVE 0x0004
+#define OPT_BACKUP 0x0008
+#define OPT_BACKUPMADE 0x0010
+#define OPT_UPDATE 0x0020
/*
* Build a path name from the specified directory name and file name.
@@ -78,15 +92,38 @@ int copyfile(char *srcname, char *destname, int setmodes)
struct stat statbuf1;
struct stat statbuf2;
struct utimbuf times;
+ static char backupname[PATHLEN];
+ /* source nonexistent */
if (stat(srcname, &statbuf1) < 0) {
perror(srcname);
return 0;
}
+ /* destination nonexistent */
if (stat(destname, &statbuf2) < 0) {
statbuf2.st_ino = -1;
statbuf2.st_dev = -1;
+ } else { /* destination existent */
+ if (ISFLAG(OPT_BACKUP)) {
+ strcpy(backupname, destname);
+ strcat(backupname, "~");
+ rename(destname, backupname);
+ SETFLAG(OPT_BACKUPMADE);
+ } else if (ISFLAG(OPT_UPDATE)) {
+ /* if dest is newer than source, don't overwrite it */
+ if (statbuf1.st_mtime < statbuf2.st_mtime) return 1;
+ } else if (ISFLAG(OPT_NOCLOBBER)) {
+ return 1;
+ } else if (ISFLAG(OPT_INTERACTIVE)) {
+ /* TODO fix this, getchar wants return */
+ /*
+ * fprintf(stderr, "really overwrite '%s'? (y/n) \n", destname);
+ if(getchar() != 'y') {
+ return -1;
+ }
+ */
+ }
}
if ((statbuf1.st_dev == statbuf2.st_dev) &&
@@ -143,9 +180,14 @@ int copyfile(char *srcname, char *destname, int setmodes)
(void) utime(destname, ×);
}
+ if (ISFLAG(OPT_BACKUPMADE) && ISFLAG(OPT_VERBOSE)) {
+ fprintf(stderr, "`%s' -> `%s' (backup: `%s')\n", srcname, destname, backupname);
+ CLRFLAG(OPT_BACKUPMADE);
+ }
+ else if (ISFLAG(OPT_VERBOSE))
+ fprintf(stderr, "`%s' -> `%s'\n", srcname, destname);
return 1;
-
error_exit:
close(rfd);
close(wfd);
@@ -157,37 +199,76 @@ error_exit:
int main(int argc, char **argv)
{
int dirflag;
+ int arg_cnt;
+ int opt_cnt;
+ int retval;
+ unsigned int file_count;
char *srcname;
char *destname;
char *lastarg;
if (argc < 3) goto usage;
+ /* lastarg is copy destination */
lastarg = argv[argc - 1];
dirflag = isadir(lastarg);
- if ((argc > 3) && !dirflag) {
- fprintf(stderr, "%s: not a directory\n", lastarg);
+ flags = 0;
+ opt_cnt = 0;
+
+ arg_cnt = 1; /* start at argv[1] */
+ while(arg_cnt < argc) {
+ if (!strcmp(argv[arg_cnt], "-n")) {
+ SETFLAG(OPT_NOCLOBBER);
+ } else if (!strcmp(argv[arg_cnt], "-v")) {
+ SETFLAG(OPT_VERBOSE);
+ } else if (!strcmp(argv[arg_cnt], "-i")) {
+ SETFLAG(OPT_INTERACTIVE);
+ } else if (!strcmp(argv[arg_cnt], "-u")) {
+ SETFLAG(OPT_UPDATE);
+ } else if (!strcmp(argv[arg_cnt], "-b")) {
+ SETFLAG(OPT_BACKUP);
+ } else if (!strcmp(argv[arg_cnt], "-h")) goto usage;
+ else break;
+ opt_cnt++;
+ arg_cnt++;
+ }
+ opt_cnt++;
+
+ /* if multiple files are specified, last one must be a directory */
+ if ((argc > (opt_cnt + 2)) && !dirflag) {
+ fprintf(stderr, "%s is not a directory\n", lastarg);
exit(1);
}
buf = malloc(BUF_SIZE);
- while (argc-- > 2) {
- srcname = argv[1];
+ file_count = 0;
+ while (argc-- > (opt_cnt + 1)) {
+ srcname = argv[opt_cnt+file_count];
destname = lastarg;
if (dirflag) destname = buildname(destname, srcname);
- if (!copyfile(*++argv, destname, 0)) goto error_copy;
+ retval = copyfile(srcname, destname, 0);
+ if (!retval) goto error_copy;
+ file_count++;
}
free(buf);
+
exit(0);
error_copy:
fprintf(stderr, "Failed to copy %s -> %s\n", srcname, destname);
exit(1);
usage:
- fprintf(stderr, "usage: %s source_file dest_file\n", argv[0]);
- fprintf(stderr, " %s file1 file2 ... dest_directory\n", argv[0]);
+ fprintf(stderr, "usage: %s [options] source_file dest_file\n", argv[0]);
+ fprintf(stderr, " %s [options] file1 file2 ... dest_directory\n", argv[0]);
+ fprintf(stderr, "options: -b make a backup of each exisiting destination file\n");
+ fprintf(stderr, " -b overrides -u (update)\n");
+ fprintf(stderr, " -n no overwriting, no clobber\n");
+ fprintf(stderr, " -v be verbose\n");
+/* fprintf(stderr, " -i interactive, prompt before overwrite\n");
+ fprintf(stderr, " -b, -u and -n override interactive mode\n");*/
+ fprintf(stderr, " -u copy only if source file is newer than destination file\n");
exit(1);
}
