sh: Add setting environment variables

5 files changed, 77 insertions, 3 deletions

diff --git a/userland/minibox/utilities/sh/ast.c b/userland/minibox/utilities/sh/ast.c
index 2a8d775..d4dc400 100644
--- a/userland/minibox/utilities/sh/ast.c
+++ b/userland/minibox/utilities/sh/ast.c
@@ -26,6 +26,60 @@ struct AST *allocate_ast(void) {
   return r;
 }
 
+int token_get(struct TOKEN **token_ptr, token_type_t type) {
+  struct TOKEN *token = *token_ptr;
+  token = token->next;
+  if (!token) {
+    return 0;
+  }
+
+  if (type != token->type) {
+    return 0;
+  }
+  *token_ptr = token;
+  return 1;
+}
+
+int parse_set(struct TOKEN **token_ptr, struct AST *cur) {
+  struct TOKEN *token = *token_ptr;
+  if (TOKEN_CHARS != token->type) {
+    return 0;
+  }
+
+  if (!sv_eq(C_TO_SV("export"), token->string_rep)) {
+    return 0;
+  }
+
+  if (!token_get(&token, TOKEN_CHARS)) {
+    return 0;
+  }
+  struct TOKEN *name = token;
+  if (!token_get(&token, TOKEN_EQUAL)) {
+    return 0;
+  }
+  if (!token_get(&token, TOKEN_CHARS)) {
+    return 0;
+  }
+  struct TOKEN *value = token;
+  if (!token_get(&token, TOKEN_NEWLINE)) {
+    return 0;
+  }
+  token = token->next;
+
+  cur->type = AST_SET;
+  cur->val.type = AST_VALUE_STRING;
+  cur->val.string = name->string_rep;
+
+  cur->children = allocate_ast();
+  struct AST *child = cur->children;
+  child->type = AST_EXPRESSION;
+  child->val.type = AST_VALUE_STRING;
+  child->val.string = value->string_rep;
+
+  *token_ptr = token;
+  return 1;
+}
+
 int parse_command(struct TOKEN **token_ptr, struct AST *cur) {
   struct TOKEN *token = *token_ptr;
   if (TOKEN_CHARS != token->type) {
@@ -94,7 +148,8 @@ struct AST *generate_ast(struct TOKEN *token) {
     if (prev) {
       prev->next = cur;
     }
-    if (parse_command(&token, cur)) {
+    if (parse_set(&token, cur)) {
+    } else if (parse_command(&token, cur)) {
     } else if (TOKEN_AND == token->type) {
       cur->type = AST_CONDITIONAL_AND;
       token = token->next;
diff --git a/userland/minibox/utilities/sh/ast.h b/userland/minibox/utilities/sh/ast.h
index 0c5768f..f0a1b2b 100644
--- a/userland/minibox/utilities/sh/ast.h
+++ b/userland/minibox/utilities/sh/ast.h
@@ -15,6 +15,7 @@ struct AST_VALUE {
 
 typedef enum {
   AST_COMMAND,
+  AST_SET,
   AST_EXPRESSION,
   AST_CONDITIONAL_AND,
   AST_CONDITIONAL_NOT,
diff --git a/userland/minibox/utilities/sh/lexer.c b/userland/minibox/utilities/sh/lexer.c
index 09fc2ff..52126b4 100644
--- a/userland/minibox/utilities/sh/lexer.c
+++ b/userland/minibox/utilities/sh/lexer.c
@@ -24,7 +24,7 @@ int is_special_char(char c) {
   if (isalnum(c)) {
     return 0;
   }
-  return !(('>' != c && '|' != c && '&' != c));
+  return !(('>' != c && '|' != c && '&' != c && '=' != c));
 }
 
 int parse_chars(struct sv *code_ptr, struct TOKEN *cur) {
@@ -54,6 +54,7 @@ int parse_operand(struct sv *code_ptr, struct TOKEN *cur) {
   TRY_PARSE_STRING(">", TOKEN_STREAM);
   TRY_PARSE_STRING("|", TOKEN_PIPE);
   TRY_PARSE_STRING("&", TOKEN_BACKGROUND);
+  TRY_PARSE_STRING("=", TOKEN_EQUAL);
   TRY_PARSE_STRING("\n", TOKEN_NEWLINE);
 
   // Failed to parse
diff --git a/userland/minibox/utilities/sh/lexer.h b/userland/minibox/utilities/sh/lexer.h
index 4a7e61c..65366dc 100644
--- a/userland/minibox/utilities/sh/lexer.h
+++ b/userland/minibox/utilities/sh/lexer.h
@@ -12,6 +12,7 @@ typedef enum {
   TOKEN_STREAM,
   TOKEN_STREAM_APPEND,
   TOKEN_BACKGROUND,
+  TOKEN_EQUAL,
   TOKEN_NEWLINE,
 } token_type_t;
 
diff --git a/userland/minibox/utilities/sh/sh.c b/userland/minibox/utilities/sh/sh.c
index 3643d99..e4a701c 100644
--- a/userland/minibox/utilities/sh/sh.c
+++ b/userland/minibox/utilities/sh/sh.c
@@ -128,10 +128,26 @@ int execute_command(struct AST *ast, int input_fd) {
   return execute_binary(ast, input_fd);
 }
 
+void set_env_from_ast(struct AST *ast) {
+  assert(AST_VALUE_STRING == ast->val.type);
+  char *name = SV_TO_C(ast->val.string);
+
+  struct AST *child = ast->children;
+  assert(AST_VALUE_STRING == child->val.type);
+  char *value = SV_TO_C(child->val.string);
+
+  setenv(name, value, 1);
+
+  free(value);
+  free(name);
+}
+
 void execute_ast(struct AST *ast) {
   int rc = -1;
   for (; ast;) {
-    if (AST_COMMAND == ast->type) {
+    if (AST_SET == ast->type) {
+      set_env_from_ast(ast);
+    } else if (AST_COMMAND == ast->type) {
       rc = execute_command(ast, STDIN_FILENO);
     } else if (AST_CONDITIONAL_AND == ast->type) {
       if (0 != rc) {