Changeset 3057 in kBuild

Timestamp:

Sep 15, 2017 6:06:42 AM (8 years ago)

Author:

bird

Message:

kash: rewrite kmk_builtin_% to kmk_% on the fly to allow harmless mixing of external and builtin kmk commands.

File:

• trunk/src/kash/exec.c (modified) (5 diffs)

trunk/src/kash/exec.c

@@ -122 +122 @@
         char *cmdname;
         int e;
+        const char *argv0 = argv[0];
+        int argv0len = (int)strlen(argv0);
+        char kmkcmd[48];
 #ifdef PC_EXE_EXTS
-        int has_ext = (int)strlen(argv[0]) - 4;
+        int has_ext = argv0len - 4;
         has_ext = has_ext > 0
-            && argv[0][has_ext] == '.'
+            && argv0[has_ext] == '.'
             /* use strstr and upper/lower permuated extensions to avoid multiple strcasecmp calls. */
             && strstr("exe;" "Exe;" "EXe;" "EXE;" "ExE;" "eXe;" "eXE;" "exE;"
@@ -132 +135 @@
                       "bat;" "Bat;" "BAt;" "BAT;" "BaT;" "bAt;" "bAT;" "baT;"
                       "btm;" "Btm;" "BTm;" "BTM;" "BtM;" "bTm;" "bTM;" "btM;",
-                      argv[0] + has_ext + 1)
+                      argv0 + has_ext + 1)
                != NULL;
 #else
         const int has_ext = 1;
 #endif
-        TRACE((psh, "shellexec: argv[0]=%s idx=%d\n", argv[0], idx));
-        if (strchr(argv[0], '/') != NULL) {
-                cmdname = stalloc(psh, strlen(argv[0]) + 5);
-                strcpy(cmdname, argv[0]);
+        TRACE((psh, "shellexec: argv[0]=%s idx=%d\n", argv0, idx));
+        if (strchr(argv0, '/') != NULL) {
+                cmdname = stalloc(psh, argv0len + 5);
+                strcpy(cmdname, argv0);
                 tryexec(psh, cmdname, argv, envp, vforked, has_ext);
                 TRACE((psh, "shellexec: cmdname=%s\n", cmdname));
@@ -146 +149 @@
                 e = errno;
         } else {
+                /* Before we search the PATH, transform kmk_builtin_% to kmk_% so we don't
+                   need to be too careful mixing internal and external kmk command. */
+                if (   argv0len > 12
+                    && argv0len < 42
+                    && strncmp(argv0, "kmk_builtin_", 12) == 0
+                    && strpbrk(argv0 + 12, "./\\-:;<>") == NULL) {
+                        memcpy(kmkcmd, "kmk_", 4);
+                        memcpy(&kmkcmd[4], argv0 + 12, argv0len + 1 - 8);
+                        TRACE((psh, "shellexec: dropped '_builtin' from %s to %s\n", argv0, kmkcmd));
+                        argv0len -= 8;
+                        argv0 = kmkcmd;
+                }
+
                 e = ENOENT;
-                while ((cmdname = padvance(psh, &path, argv[0])) != NULL) {
+                while ((cmdname = padvance(psh, &path, argv0)) != NULL) {
                         if (--idx < 0 && psh->pathopt == NULL) {
                                 tryexec(psh, cmdname, argv, envp, vforked, has_ext);
@@ -553 +569 @@
         int e;
         int (*bltin)(shinstance*,int,char **);
-
+        int argv0len = (int)strlen(name);
+        char kmkcmd[48];
 #ifdef PC_EXE_EXTS
-        int has_ext = (int)(strlen(name) - 4);
+        int has_ext = argv0len - 4;
         has_ext = has_ext > 0
             && name[has_ext] == '.'
@@ -638 +655 @@
                 else
                         prev = cmdp->param.index;
+        }
+
+        /* Before we search the PATH, transform kmk_builtin_% to kmk_% so we don't
+           need to be too careful mixing internal and external kmk command. */
+        if (   argv0len > 12
+            && argv0len < (int)sizeof(kmkcmd)
+            && strncmp(name, "kmk_builtin_", 12) == 0
+            && strpbrk(name + 12, "./\\-:;<>") == NULL) {
+                memcpy(kmkcmd, "kmk_", 4);
+                memcpy(&kmkcmd[4], name + 12, argv0len + 1 - 8);
+                TRACE((psh, "find_command: dropped '_builtin' from %s to %s\n", name, kmkcmd));
+                argv0len -= 8;
+                name = kmkcmd;
         }