shared/escape: add new escape style with \n\t escaped

3 files changed, 30 insertions, 8 deletions

diff --git a/src/basic/escape.c b/src/basic/escape.c
index c5c44d2e7d..116efa4119 100644
--- a/src/basic/escape.c
+++ b/src/basic/escape.c
@@ -518,22 +518,28 @@ char* shell_maybe_quote(const char *s, EscapeStyle style) {
                 return NULL;
 
         t = r;
-        if (style == ESCAPE_BACKSLASH)
+        switch (style) {
+        case ESCAPE_BACKSLASH:
+        case ESCAPE_BACKSLASH_ONELINE:
                 *(t++) = '"';
-        else if (style == ESCAPE_POSIX) {
+                break;
+        case ESCAPE_POSIX:
                 *(t++) = '$';
                 *(t++) = '\'';
-        } else
+                break;
+        default:
                 assert_not_reached("Bad EscapeStyle");
+        }
 
         t = mempcpy(t, s, p - s);
 
-        if (style == ESCAPE_BACKSLASH)
-                t = strcpy_backslash_escaped(t, p, SHELL_NEED_ESCAPE, false);
+        if (IN_SET(style, ESCAPE_BACKSLASH, ESCAPE_BACKSLASH_ONELINE))
+                t = strcpy_backslash_escaped(t, p, SHELL_NEED_ESCAPE,
+                                             style == ESCAPE_BACKSLASH_ONELINE);
         else
                 t = strcpy_backslash_escaped(t, p, SHELL_NEED_ESCAPE_POSIX, true);
 
-        if (style == ESCAPE_BACKSLASH)
+        if (IN_SET(style, ESCAPE_BACKSLASH, ESCAPE_BACKSLASH_ONELINE))
                 *(t++) = '"';
         else
                 *(t++) = '\'';
diff --git a/src/basic/escape.h b/src/basic/escape.h
index b8eb137c3d..0b00b116ed 100644
--- a/src/basic/escape.h
+++ b/src/basic/escape.h
@@ -34,8 +34,13 @@ typedef enum UnescapeFlags {
 } UnescapeFlags;
 
 typedef enum EscapeStyle {
-        ESCAPE_BACKSLASH = 1,
-        ESCAPE_POSIX     = 2,
+        ESCAPE_BACKSLASH         = 1,  /* Add shell quotes ("") so the shell will consider this a single
+                                          argument, possibly multiline. Tabs and newlines are not escaped. */
+        ESCAPE_BACKSLASH_ONELINE = 2,  /* Similar to ESCAPE_BACKSLASH, but always produces a single-line
+                                          string instead. Shell escape sequences are produced for tabs and
+                                          newlines. */
+        ESCAPE_POSIX             = 3,  /* Similar to ESCAPE_BACKSLASH_ONELINE, but uses POSIX shell escape
+                                        * syntax (a string enclosed in $'') instead of plain quotes. */
 } EscapeStyle;
 
 char *cescape(const char *s);
diff --git a/src/test/test-escape.c b/src/test/test-escape.c
index f6aae1eb18..699747fcc3 100644
--- a/src/test/test-escape.c
+++ b/src/test/test-escape.c
@@ -142,31 +142,42 @@ static void test_shell_maybe_quote_one(const char *s,
 static void test_shell_maybe_quote(void) {
 
         test_shell_maybe_quote_one("", ESCAPE_BACKSLASH, "");
+        test_shell_maybe_quote_one("", ESCAPE_BACKSLASH_ONELINE, "");
         test_shell_maybe_quote_one("", ESCAPE_POSIX, "");
         test_shell_maybe_quote_one("\\", ESCAPE_BACKSLASH, "\"\\\\\"");
+        test_shell_maybe_quote_one("\\", ESCAPE_BACKSLASH_ONELINE, "\"\\\\\"");
         test_shell_maybe_quote_one("\\", ESCAPE_POSIX, "$'\\\\'");
         test_shell_maybe_quote_one("\"", ESCAPE_BACKSLASH, "\"\\\"\"");
+        test_shell_maybe_quote_one("\"", ESCAPE_BACKSLASH_ONELINE, "\"\\\"\"");
         test_shell_maybe_quote_one("\"", ESCAPE_POSIX, "$'\"'");
         test_shell_maybe_quote_one("foobar", ESCAPE_BACKSLASH, "foobar");
+        test_shell_maybe_quote_one("foobar", ESCAPE_BACKSLASH_ONELINE, "foobar");
         test_shell_maybe_quote_one("foobar", ESCAPE_POSIX, "foobar");
         test_shell_maybe_quote_one("foo bar", ESCAPE_BACKSLASH, "\"foo bar\"");
+        test_shell_maybe_quote_one("foo bar", ESCAPE_BACKSLASH_ONELINE, "\"foo bar\"");
         test_shell_maybe_quote_one("foo bar", ESCAPE_POSIX, "$'foo bar'");
         test_shell_maybe_quote_one("foo\tbar", ESCAPE_BACKSLASH, "\"foo\tbar\"");
+        test_shell_maybe_quote_one("foo\tbar", ESCAPE_BACKSLASH_ONELINE, "\"foo\\tbar\"");
         test_shell_maybe_quote_one("foo\tbar", ESCAPE_POSIX, "$'foo\\tbar'");
         test_shell_maybe_quote_one("foo\nbar", ESCAPE_BACKSLASH, "\"foo\nbar\"");
+        test_shell_maybe_quote_one("foo\nbar", ESCAPE_BACKSLASH_ONELINE, "\"foo\\nbar\"");
         test_shell_maybe_quote_one("foo\nbar", ESCAPE_POSIX, "$'foo\\nbar'");
         test_shell_maybe_quote_one("foo \"bar\" waldo", ESCAPE_BACKSLASH, "\"foo \\\"bar\\\" waldo\"");
+        test_shell_maybe_quote_one("foo \"bar\" waldo", ESCAPE_BACKSLASH_ONELINE, "\"foo \\\"bar\\\" waldo\"");
         test_shell_maybe_quote_one("foo \"bar\" waldo", ESCAPE_POSIX, "$'foo \"bar\" waldo'");
         test_shell_maybe_quote_one("foo$bar", ESCAPE_BACKSLASH, "\"foo\\$bar\"");
+        test_shell_maybe_quote_one("foo$bar", ESCAPE_BACKSLASH_ONELINE, "\"foo\\$bar\"");
         test_shell_maybe_quote_one("foo$bar", ESCAPE_POSIX, "$'foo$bar'");
 
         /* Note that current users disallow control characters, so this "test"
          * is here merely to establish current behaviour. If control characters
          * were allowed, they should be quoted, i.e. \001 should become \\001. */
         test_shell_maybe_quote_one("a\nb\001", ESCAPE_BACKSLASH, "\"a\nb\001\"");
+        test_shell_maybe_quote_one("a\nb\001", ESCAPE_BACKSLASH_ONELINE, "\"a\\nb\001\"");
         test_shell_maybe_quote_one("a\nb\001", ESCAPE_POSIX, "$'a\\nb\001'");
 
         test_shell_maybe_quote_one("foo!bar", ESCAPE_BACKSLASH, "\"foo!bar\"");
+        test_shell_maybe_quote_one("foo!bar", ESCAPE_BACKSLASH_ONELINE, "\"foo!bar\"");
         test_shell_maybe_quote_one("foo!bar", ESCAPE_POSIX, "$'foo!bar'");
 }