Add ask() as a way to get user input

3 files changed, 54 insertions, 2 deletions

diff --git a/builtins/functions.c b/builtins/functions.c
index 27bb06f8..b69f81d9 100644
--- a/builtins/functions.c
+++ b/builtins/functions.c
@@ -246,6 +246,48 @@ public void say(Text_t text, bool newline)
         fputc('\n', stdout);
 }
 
+public Text_t ask(Text_t prompt, bool bold, bool force_tty)
+{
+    Text_t ret = Text("");
+    FILE *out = stdout;
+    FILE *in = stdin;
+
+    if (force_tty && !isatty(STDOUT_FILENO)) {
+        out = fopen("/dev/tty", "w");
+        if (!out) goto cleanup;
+    }
+
+    if (bold) fputs("\x1b[1m", out);
+    Text$print(out, prompt);
+    if (bold) fputs("\x1b[m", out);
+    fflush(out);
+
+    if (force_tty && !isatty(STDIN_FILENO)) {
+        in = fopen("/dev/tty", "r");
+        if (!in) goto cleanup;
+    }
+
+    char *line = NULL;
+    size_t bufsize = 0;
+    ssize_t length = getline(&line, &bufsize, in);
+    if (length == -1) goto cleanup;
+
+    if (length > 0 && line[length-1] == '\n') {
+        line[length-1] = '\0';
+        --length;
+    }
+
+    char *gc_input = GC_MALLOC_ATOMIC(length + 1);
+    memcpy(gc_input, line, length + 1);
+
+    ret = Text$from_strn(gc_input, length);
+
+  cleanup:
+    if (out && out != stdout) fclose(out);
+    if (in && in != stdin) fclose(in);
+    return ret;
+}
+
 public bool pop_flag(char **argv, int *i, const char *flag, Text_t *result)
 {
     if (argv[*i][0] != '-' || argv[*i][1] != '-') {
diff --git a/builtins/functions.h b/builtins/functions.h
index 263255f4..c9db6ea8 100644
--- a/builtins/functions.h
+++ b/builtins/functions.h
@@ -22,6 +22,7 @@ void end_test(const void *expr, const TypeInfo *type, const char *expected, cons
     start_test(__SOURCE_FILE__, start, end); \
     end_test((__typeof__(expr)[1]){expr}, typeinfo, expected, __SOURCE_FILE__, start, end); }
 void say(Text_t text, bool newline);
+Text_t ask(Text_t prompt, bool bold, bool force_tty);
 
 uint64_t generic_hash(const void *obj, const TypeInfo *type);
 int32_t generic_compare(const void *x, const void *y, const TypeInfo *type);
diff --git a/environment.c b/environment.c
index eb456030..32e3f7f6 100644
--- a/environment.c
+++ b/environment.c
@@ -30,8 +30,17 @@ env_t *new_compilation_unit(CORD *libname)
         const char *name;
         binding_t binding;
     } global_vars[] = {
-        {"say", {.code="say", .type=Type(FunctionType, .args=new(arg_t, .name="text", .type=TEXT_TYPE,
-                                                                 .next=new(arg_t, .name="newline", .type=Type(BoolType), .default_val=FakeAST(Bool, true))), .ret=Type(VoidType))}},
+        {"say", {.code="say", .type=Type(
+                    FunctionType, .args=new(arg_t, .name="text", .type=TEXT_TYPE,
+                                            .next=new(arg_t, .name="newline", .type=Type(BoolType), .default_val=FakeAST(Bool, true))),
+                    .ret=Type(VoidType))}},
+        {"ask", {.code="ask", .type=Type(
+                    FunctionType, .args=new(arg_t, .name="prompt", .type=TEXT_TYPE,
+                                            .next=new(arg_t, .name="bold", .type=Type(BoolType),
+                                                      .default_val=FakeAST(Bool, true),
+                                                      .next=new(arg_t, .name="force_tty", .type=Type(BoolType),
+                                                                .default_val=FakeAST(Bool, true)))),
+                    .ret=TEXT_TYPE)}},
         {"fail", {.code="fail", .type=Type(FunctionType, .args=new(arg_t, .name="message", .type=Type(CStringType)), .ret=Type(AbortType))}},
         {"USE_COLOR", {.code="USE_COLOR", .type=Type(BoolType)}},
     };