From b10fa984f36786466476bc325c310f21b8c662d1 Mon Sep 17 00:00:00 2001
From: jD91mZM2 <me@krake.one>
Date: Thu, 9 Aug 2018 16:34:28 +0200
Subject: [PATCH] Implement strtod
---
src/stdlib/src/lib.rs | 54 ++++++++++++++++++++++++-----
tests/Makefile | 1 +
tests/expected/stdio/all.stdout | 1 +
tests/expected/stdio/setvbuf.stderr | 0
tests/expected/stdio/setvbuf.stdout | 6 ++++
tests/expected/stdlib/strtod.stderr | 0
tests/expected/stdlib/strtod.stdout | 9 +++++
tests/stdlib/strtod.c | 17 +++++++++
8 files changed, 79 insertions(+), 9 deletions(-)
create mode 100644 tests/expected/stdio/setvbuf.stderr
create mode 100644 tests/expected/stdio/setvbuf.stdout
create mode 100644 tests/expected/stdlib/strtod.stderr
create mode 100644 tests/expected/stdlib/strtod.stdout
create mode 100644 tests/stdlib/strtod.c
diff --git a/src/stdlib/src/lib.rs b/src/stdlib/src/lib.rs
index d60ffc8a..9a9cfe8e 100644
--- a/src/stdlib/src/lib.rs
+++ b/src/stdlib/src/lib.rs
@@ -635,19 +635,55 @@ pub extern "C" fn srandom(seed: c_uint) {
}
#[no_mangle]
-pub unsafe extern "C" fn strtod(s: *const c_char, endptr: *mut *mut c_char) -> c_double {
- // TODO: endptr
+pub unsafe extern "C" fn strtod(mut s: *const c_char, endptr: *mut *mut c_char) -> c_double {
+ while ctype::isspace(*s as c_int) != 0 {
+ s = s.offset(1);
+ }
- use core::str::FromStr;
+ let mut result = 0.0;
+ let mut radix = 10;
- let s_str = str::from_utf8_unchecked(platform::c_str(s));
- match f64::from_str(s_str) {
- Ok(ok) => ok as c_double,
- Err(_err) => {
- platform::errno = EINVAL;
- 0.0
+ let negative = match *s as u8 {
+ b'-' => { s = s.offset(1); true },
+ b'+' => { s = s.offset(1); false },
+ _ => false
+ };
+
+ if *s as u8 == b'0' && *s.offset(1) as u8 == b'x' {
+ s = s.offset(2);
+ radix = 16;
+ }
+
+ while let Some(digit) = (*s as u8 as char).to_digit(radix) {
+ result *= radix as c_double;
+ result += digit as c_double;
+ s = s.offset(1);
+ }
+
+ if *s as u8 == b'.' {
+ s = s.offset(1);
+
+ let mut i = 1.0;
+ while let Some(digit) = (*s as u8 as char).to_digit(radix) {
+ i *= radix as c_double;
+ result += digit as c_double / i;
+ s = s.offset(1);
}
}
+
+ if !endptr.is_null() {
+ // This is stupid, but apparently strto* functions want
+ // const input but mut output, yet the man page says
+ // "stores the address of the first invalid character in *endptr"
+ // so obviously it doesn't want us to clone it.
+ *endptr = s as *mut _;
+ }
+
+ if negative {
+ -result
+ } else {
+ result
+ }
}
pub fn is_positive(ch: c_char) -> Option<(bool, isize)> {
diff --git a/tests/Makefile b/tests/Makefile
index b6eacd63..33fd0564 100644
--- a/tests/Makefile
+++ b/tests/Makefile
@@ -28,6 +28,7 @@ EXPECT_BINS=\
stdlib/env \
stdlib/mkostemps \
stdlib/rand \
+ stdlib/strtod \
stdlib/strtol \
stdlib/strtoul \
stdlib/system \
diff --git a/tests/expected/stdio/all.stdout b/tests/expected/stdio/all.stdout
index 23bfb625..ebda98d0 100644
--- a/tests/expected/stdio/all.stdout
+++ b/tests/expected/stdio/all.stdout
@@ -1,3 +1,4 @@
H
Hello World!
+Hello
diff --git a/tests/expected/stdio/setvbuf.stderr b/tests/expected/stdio/setvbuf.stderr
new file mode 100644
index 00000000..e69de29b
diff --git a/tests/expected/stdio/setvbuf.stdout b/tests/expected/stdio/setvbuf.stdout
new file mode 100644
index 00000000..7f04b787
--- /dev/null
+++ b/tests/expected/stdio/setvbuf.stdout
@@ -0,0 +1,6 @@
+H
+ello World!
+
+Line 2
+
+Hello
diff --git a/tests/expected/stdlib/strtod.stderr b/tests/expected/stdlib/strtod.stderr
new file mode 100644
index 00000000..e69de29b
diff --git a/tests/expected/stdlib/strtod.stdout b/tests/expected/stdlib/strtod.stdout
new file mode 100644
index 00000000..c3013b85
--- /dev/null
+++ b/tests/expected/stdlib/strtod.stdout
@@ -0,0 +1,9 @@
+d: 0 Endptr: "a 1 hello"
+d: 1 Endptr: " hello"
+d: 1 Endptr: " hello 2"
+d: 10.123 Endptr: ""
+d: 10.123 Endptr: ""
+d: -5.3 Endptr: ""
+d: 16.071044921875 Endptr: ""
+d: 1.13671875 Endptr: ""
+d: 3.12890625 Endptr: ""
diff --git a/tests/stdlib/strtod.c b/tests/stdlib/strtod.c
new file mode 100644
index 00000000..21a72805
--- /dev/null
+++ b/tests/stdlib/strtod.c
@@ -0,0 +1,17 @@
+#include <stdlib.h>
+#include <stdio.h>
+
+int main() {
+ char* endptr = 0;
+ double d;
+
+ char* inputs[] = {
+ "a 1 hello", " 1 hello", "1 hello 2",
+ "10.123", "010.123", "-5.3",
+ "0x10.123", "0x1.23", "0x3.21"
+ };
+ for (int i = 0; i < sizeof(inputs) / sizeof(char*); i += 1) {
+ d = strtod(inputs[i], &endptr);
+ printf("d: %f Endptr: \"%s\"\n", d, endptr);
+ }
+}
--
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