ash: fix ${var/s/r} handling, add testcase.

3 files changed, 75 insertions, 61 deletions

diff --git a/shell/ash.c b/shell/ash.c
index a8428b9dc..0913a2f41 100644
--- a/shell/ash.c
+++ b/shell/ash.c
@@ -5818,73 +5818,26 @@ parse_sub_pattern(char *arg, int inquotes)
         char *idx, *repl = NULL;
         unsigned char c;
 
-        for (idx = arg; *arg; arg++) {
-                if (*arg == '/') {
-                        /* Only the first '/' seen is our seperator */
+        idx = arg;
+        while (1) {
+                c = *arg;
+                if (!c)
+                        break;
+                if (c == '/') {
+                        /* Only the first '/' seen is our separator */
                         if (!repl) {
-                                *idx++ = '\0';
-                                repl = idx;
-                        } else
-                                *idx++ = *arg;
-                        } else if (*arg != '\\') {
-                                *idx++ = *arg;
-                        } else {
-                                if (inquotes)
-                                        arg++;
-                                else {
-                                        if (*(arg + 1) != '\\')
-                                                goto single_backslash;
-                                        arg += 2;
-                                }
-
-                        switch (*arg) {
-                        case 'n':       c = '\n'; break;
-                        case 'r':       c = '\r'; break;
-                        case 't':       c = '\t'; break;
-                        case 'v':       c = '\v'; break;
-                        case 'f':       c = '\f'; break;
-                        case 'b':       c = '\b'; break;
-                        case 'a':       c = '\a'; break;
-                        case '\\':
-                                if (*(arg + 1) != '\\' && !inquotes)
-                                        goto single_backslash;
-                                arg++;
-                                /* FALLTHROUGH */
-                        case '\0':
-                                /* Trailing backslash, just stuff one in the buffer
-                                 * and backup arg so the loop will exit.
-                                 */
-                                c = '\\';
-                                if (!*arg)
-                                        arg--;
-                                break;
-                        default:
-                                c = *arg;
-                                if (isdigit(c)) {
-                                        /* It's an octal number, parse it. */
-                                        int i;
-                                        c = 0;
-
-                                        for (i = 0; *arg && i < 3; arg++, i++) {
-                                                if (*arg >= '8' || *arg < '0')
-                                                        ash_msg_and_raise_error("Invalid octal char in pattern");
-// TODO: number() instead? It does error checking...
-                                                c = (c << 3) + atoi(arg);
-                                        }
-                                        /* back off one (so outer loop can do it) */
-                                        arg--;
-                                }
+                                repl = idx + 1;
+                                c = '\0';
                         }
-                        *idx++ = c;
                 }
+                *idx++ = c;
+                if (!inquotes && c == '\\' && arg[1] == '\\')
+                        arg++; /* skip both \\, not just first one */
+                arg++;
         }
-        *idx = *arg;
+        *idx++ = c;
 
         return repl;
-
- single_backslash:
-        ash_msg_and_raise_error("single backslash unexpected");
-        /* NOTREACHED */
 }
 #endif /* ENABLE_ASH_BASH_COMPAT */
 
diff --git a/shell/ash_test/ash-vars/var_bash3.right b/shell/ash_test/ash-vars/var_bash3.right
new file mode 100644
index 000000000..f7f14791e
--- /dev/null
+++ b/shell/ash_test/ash-vars/var_bash3.right
@@ -0,0 +1,20 @@
+a041#c
+a041#c
+a\041#c
+a\041#c
+a\041#c
+a\041#c
+a\041#c
+a\041#c
+a\041#c
+a\c
+a\c
+a\c
+a\\c
+a\\c
+a\\c
+a\tc
+a\tc
+a\tc
+atc
+a\tc
diff --git a/shell/ash_test/ash-vars/var_bash3.tests b/shell/ash_test/ash-vars/var_bash3.tests
new file mode 100755
index 000000000..b9050279e
--- /dev/null
+++ b/shell/ash_test/ash-vars/var_bash3.tests
@@ -0,0 +1,41 @@
+a='abc'
+r=${a//b/\041#}
+echo $r
+echo ${a//b/\041#}
+echo "${a//b/\041#}"
+
+a='abc'
+r=${a//b/\\041#}
+echo $r
+echo ${a//b/\\041#}
+echo "${a//b/\\041#}"
+
+a='abc'
+b='\041#'
+r=${a//b/$b}
+echo $r
+echo ${a//b/$b}
+echo "${a//b/$b}"
+
+a='abc'
+b='\'
+r="${a//b/$b}"
+echo $r
+echo ${a//b/$b}
+echo "${a//b/$b}"
+
+a='abc'
+b='\\'
+r="${a//b/$b}"
+echo $r
+echo ${a//b/$b}
+echo "${a//b/$b}"
+
+a='abc'
+b='\t'
+r="${a//b/$b}"
+echo $r
+echo ${a//b/$b}
+echo "${a//b/$b}"
+echo ${a//b/\t}
+echo "${a//b/\t}"