Add basic branching support, sed ':' and 'b' commands

diff --git a/editors/sed.c b/editors/sed.c
index 037d2a8ac8c0474f00a85b3851dd51276c2e5e25..5fe435622b633d155360e43f911a849a00c612e2 100644 (file)
--- a/editors/sed.c
+++ b/editors/sed.c
@@ -55,6 +55,9 @@
 #include <stdlib.h>
 #include "busybox.h"
 
+/* the spec says label must be at least 8 chars, behavious is unspecified if more than 8 chars */
+#define SED_LABEL_LENGTH       8
+
 /* externs */
 extern void xregcomp(regex_t *preg, const char *regex, int cflags);
 extern int optind; /* in unistd.h */
@@ -103,6 +106,9 @@ typedef struct sed_cmd_s {
        /* inversion flag */
        int invert;         /* the '!' after the address */
 
+       /* Branch commands */
+       char label[SED_LABEL_LENGTH + 1];
+
        /* next command in list (sequential list of specified commands) */
        struct sed_cmd_s *linear;
 
@@ -399,6 +405,18 @@ static char *parse_cmd_str(sed_cmd_t * const sed_cmd, char *cmdstr)
                        bb_error_msg_and_die("Command only uses one address");
                cmdstr += parse_file_cmd(sed_cmd, cmdstr);
        }
+       /* handle branch commands */
+       else if (strchr(":b", sed_cmd->cmd)) {
+               int length;
+
+               cmdstr += strspn(cmdstr, " ");
+               length = strcspn(cmdstr, "; ");
+               if (length > SED_LABEL_LENGTH) {
+                       length = SED_LABEL_LENGTH;
+               }
+               strncpy(sed_cmd->label, cmdstr, length);
+        cmdstr += length;
+       }
        /* if it wasnt a single-letter command that takes no arguments
         * then it must be an invalid command.
         */
@@ -677,6 +695,18 @@ static int do_subst_command(const sed_cmd_t *sed_cmd, char **line)
        return altered;
 }
 
+static sed_cmd_t *branch_to(const char *label)
+{
+       sed_cmd_t *sed_cmd;
+       for(sed_cmd = sed_cmd_head.linear; sed_cmd; sed_cmd = sed_cmd->linear) {
+               if (strcmp(sed_cmd->label, label) == 0) {
+                       break;
+               }
+       }
+
+       /* If no match returns last command */
+       return(sed_cmd);
+}
 
 static void process_file(FILE *file)
 {
@@ -832,6 +862,12 @@ static void process_file(FILE *file)
                                                strcat(line, next_line);
                                                next_line = bb_get_chomped_line_from_file(file);
                                                linenum++;
+                                               break;
+                                       case 'b':
+                                               sed_cmd = branch_to(sed_cmd->label);
+                                               break;
+//                                     case ':':
+//                                             break;
                                }
                        }