ignore-case.diff

This adds the --ignore-case option, which makes rsync compare filenames
in a case-insensitive manner.

To use this patch, run these commands for a successful build:

    patch -p1 <patches/ignore-case.diff
    ./configure                            (optional if already run)
    make

TODO:

 - Make this code handle multibyte character encodings, and honor the
   --iconv setting when converting case.

based-on: 6c8ca91c731b7bf2b081694bda85b7dadc2b7aff
diff --git a/exclude.c b/exclude.c
--- a/exclude.c
+++ b/exclude.c
@@ -966,16 +966,15 @@ static int rule_matches(const char *fname, filter_rule *ex, int name_flags)
 		if (litmatch_array(pattern, strings, slash_handling))
 			return ret_match;
 	} else if (anchored_match) {
-		if (strcmp(name, pattern) == 0)
+		if (ic_strEQ(name, pattern))
 			return ret_match;
 	} else {
 		int l1 = strlen(name);
 		int l2 = strlen(pattern);
-		if (l2 <= l1 &&
-		    strcmp(name+(l1-l2),pattern) == 0 &&
-		    (l1==l2 || name[l1-(l2+1)] == '/')) {
+		if (l2 <= l1
+		 && ic_strEQ(name + (l1-l2), pattern)
+		 && (l1 == l2 || name[l1 - (l2+1)] == '/'))
 			return ret_match;
-		}
 	}
 
 	return !ret_match;
diff --git a/flist.c b/flist.c
--- a/flist.c
+++ b/flist.c
@@ -34,6 +34,7 @@ extern int am_generator;
 extern int inc_recurse;
 extern int always_checksum;
 extern int module_id;
+extern int ignore_case;
 extern int ignore_errors;
 extern int numeric_ids;
 extern int quiet;
@@ -2638,7 +2639,8 @@ struct file_list *recv_file_list(int f, int dir_ndx)
 				cur_dir++;
 			if (cur_dir != good_dirname) {
 				const char *d = dir_ndx >= 0 ? f_name(dir_flist->files[dir_ndx], NULL) : empty_dir;
-				if (strcmp(cur_dir, d) != 0) {
+				int dir_differs = ignore_case ? strcasecmp(cur_dir, d) : strcmp(cur_dir, d);
+				if (dir_differs) {
 					rprintf(FERROR,
 						"ABORTING due to invalid path from sender: %s/%s\n",
 						cur_dir, file->basename);
@@ -3205,6 +3207,7 @@ int f_name_cmp(const struct file_struct *f1, const struct file_struct *f2)
 {
 	int dif;
 	const uchar *c1, *c2;
+	uchar ch1, ch2;
 	enum fnc_state state1, state2;
 	enum fnc_type type1, type2;
 	enum fnc_type t_path = protocol_version >= 29 ? t_PATH : t_ITEM;
@@ -3315,7 +3318,15 @@ int f_name_cmp(const struct file_struct *f1, const struct file_struct *f2)
 			if (type1 != type2)
 				return type1 == t_PATH ? 1 : -1;
 		}
-	} while ((dif = (int)*c1++ - (int)*c2++) == 0);
+		ch1 = *c1++;
+		ch2 = *c2++;
+		if (ignore_case) {
+			if (isupper(ch1))
+				ch1 = tolower(ch1);
+			if (isupper(ch2))
+				ch2 = tolower(ch2);
+		}
+	} while ((dif = (int)ch1 - (int)ch2) == 0);
 
 	return dif;
 }
diff --git a/ifuncs.h b/ifuncs.h
--- a/ifuncs.h
+++ b/ifuncs.h
@@ -110,3 +110,38 @@ static inline char *my_strdup(const char *str, const char *file, int line)
     memcpy(buf, str, len);
     return buf;
 }
+
+static inline int
+strEQ(const char *s1, const char *s2)
+{
+	return strcmp(s1, s2) == 0;
+}
+
+static inline int
+strnEQ(const char *s1, const char *s2, size_t n)
+{
+	return strncmp(s1, s2, n) == 0;
+}
+
+static inline int
+ic_strEQ(const char *s1, const char *s2)
+{
+	extern int ignore_case;
+	if (ignore_case)
+		return strcasecmp(s1, s2) == 0;
+	return strcmp(s1, s2) == 0;
+}
+
+static inline int
+ic_strnEQ(const char *s1, const char *s2, size_t n)
+{
+	extern int ignore_case;
+	if (ignore_case)
+		return strncasecmp(s1, s2, n) == 0;
+	return strncmp(s1, s2, n) == 0;
+}
+
+#define strNE(s1,s2) (!strEQ(s1,s2))
+#define strnNE(s1,s2,n) (!strnEQ(s1,s2,n))
+#define ic_strNE(s1,s2) (!ic_strEQ(s1,s2))
+#define ic_strnNE(s1,s2) (!ic_strnEQ(s1,s2,n))
diff --git a/lib/wildmatch.c b/lib/wildmatch.c
--- a/lib/wildmatch.c
+++ b/lib/wildmatch.c
@@ -53,6 +53,8 @@
 #define ISUPPER(c) (ISASCII(c) && isupper(c))
 #define ISXDIGIT(c) (ISASCII(c) && isxdigit(c))
 
+extern int ignore_case;
+
 #ifdef WILD_TEST_ITERATIONS
 int wildmatch_iteration_count;
 #endif
@@ -72,6 +74,8 @@ static int dowild(const uchar *p, const uchar *text, const uchar*const *a)
     for ( ; (p_ch = *p) != '\0'; text++, p++) {
 	int matched, special;
 	uchar t_ch, prev_ch;
+	if (ignore_case && ISUPPER(p_ch))
+	    p_ch = tolower(p_ch);
 	while ((t_ch = *text) == '\0') {
 	    if (*a == NULL) {
 		if (p_ch != '*')
@@ -237,12 +241,21 @@ static int dowild(const uchar *p, const uchar *text, const uchar*const *a)
  * of "text" and any strings in array "a". */
 static int doliteral(const uchar *s, const uchar *text, const uchar*const *a)
 {
+    uchar s_ch, t_ch;
     for ( ; *s != '\0'; text++, s++) {
 	while (*text == '\0') {
 	    if ((text = *a++) == NULL)
 		return FALSE;
 	}
-	if (*text != *s)
+	s_ch = *s;
+	t_ch = *text;
+	if (ignore_case) {
+	    if (ISUPPER(s_ch))
+		s_ch = tolower(s_ch);
+	    if (ISUPPER(t_ch))
+		t_ch = tolower(t_ch);
+	}
+	if (t_ch != s_ch)
 	    return FALSE;
     }
 
@@ -288,10 +301,14 @@ static const uchar *trailing_N_elements(const uchar*const **a_ptr, int count)
 int wildmatch(const char *pattern, const char *text)
 {
     static const uchar *nomore[1]; /* A NULL pointer. */
+    int ret;
 #ifdef WILD_TEST_ITERATIONS
     wildmatch_iteration_count = 0;
 #endif
-    return dowild((const uchar*)pattern, (const uchar*)text, nomore) == TRUE;
+    force_lower_case = ignore_case;
+    ret = dowild((const uchar*)pattern, (const uchar*)text, nomore) == TRUE;
+    force_lower_case = 0;
+    return ret;
 }
 
 /* Match the "pattern" against the forced-to-lower-case "text" string. */
@@ -331,12 +348,14 @@ int wildmatch_array(const char *pattern, const char*const *texts, int where)
     if (!text)
 	return FALSE;
 
+    force_lower_case = ignore_case;
+
     if ((matched = dowild(p, text, a)) != TRUE && where < 0
      && matched != ABORT_ALL) {
 	while (1) {
 	    if (*text == '\0') {
 		if ((text = (uchar*)*a++) == NULL)
-		    return FALSE;
+		    break;
 		continue;
 	    }
 	    if (*text++ == '/' && (matched = dowild(p, text, a)) != FALSE
@@ -344,6 +363,9 @@ int wildmatch_array(const char *pattern, const char*const *texts, int where)
 		break;
 	}
     }
+
+    force_lower_case = 0;
+
     return matched == TRUE;
 }
 
diff --git a/options.c b/options.c
--- a/options.c
+++ b/options.c
@@ -131,6 +131,7 @@ OFF_T max_size = -1;
 OFF_T min_size = -1;
 int ignore_errors = 0;
 int modify_window = 0;
+int ignore_case = 0;
 int blocking_io = -1;
 int checksum_seed = 0;
 int inplace = 0;
@@ -784,6 +785,8 @@ static struct poptOption long_options[] = {
   {"read-batch",       0,  POPT_ARG_STRING, &batch_name, OPT_READ_BATCH, 0, 0 },
   {"write-batch",      0,  POPT_ARG_STRING, &batch_name, OPT_WRITE_BATCH, 0, 0 },
   {"only-write-batch", 0,  POPT_ARG_STRING, &batch_name, OPT_ONLY_WRITE_BATCH, 0, 0 },
+  {"ignore-case",      0,  POPT_ARG_VAL,    &ignore_case, 1, 0, 0 },
+  {"no-ignore-case",   0,  POPT_ARG_VAL,    &ignore_case, 0, 0, 0 },
   {"files-from",       0,  POPT_ARG_STRING, &files_from, 0, 0, 0 },
   {"from0",           '0', POPT_ARG_VAL,    &eol_nulls, 1, 0, 0},
   {"no-from0",         0,  POPT_ARG_VAL,    &eol_nulls, 0, 0, 0},
@@ -2865,6 +2868,9 @@ void server_options(char **args, int *argc_p)
 		args[ac++] = arg;
 	}
 
+	if (ignore_case)
+		args[ac++] = "--ignore-case";
+
 	if (partial_dir && am_sender) {
 		if (partial_dir != tmp_partialdir) {
 			args[ac++] = "--partial-dir";
diff --git a/rsync.1.md b/rsync.1.md
--- a/rsync.1.md
+++ b/rsync.1.md
@@ -528,6 +528,7 @@ has its own detailed description later in this manpage.
 --secluded-args, -s      use the protocol to safely send the args
 --trust-sender           trust the remote sender's file list
 --copy-as=USER[:GROUP]   specify user & optional group for the copy
+--ignore-case            ignore case when comparing filenames
 --address=ADDRESS        bind address for outgoing socket to daemon
 --port=PORT              specify double-colon alternate port number
 --sockopts=OPTIONS       specify custom TCP options
@@ -2583,6 +2584,12 @@ expand it.
 
     >     sudo rsync -aive lsh -M--copy-as=joe src/ lh:dest/
 
+0.  `--ignore-case`
+
+    This option tells rsync to ignore upper-/lower-case differences when
+    comparing filenames.  This can avoid problems when sending files to a
+    filesystem that ignores these differences.
+
 0.  `--temp-dir=DIR`, `-T`
 
     This option instructs rsync to use DIR as a scratch directory when creating
diff --git a/t_stub.c b/t_stub.c
--- a/t_stub.c
+++ b/t_stub.c
@@ -34,6 +34,7 @@ int preserve_perms = 0;
 int preserve_executability = 0;
 int omit_link_times = 0;
 int open_noatime = 0;
+int ignore_case = 0;
 size_t max_alloc = 0; /* max_alloc is needed when combined with util2.o */
 char *partial_dir;
 char *module_dir;
diff --git a/wildtest.c b/wildtest.c
--- a/wildtest.c
+++ b/wildtest.c
@@ -30,6 +30,7 @@
 int fnmatch_errors = 0;
 #endif
 
+int ignore_case = 0;
 int wildmatch_errors = 0;
 
 typedef char bool;