From 8e97b754aaef36293efea7e777593306621948e0 Mon Sep 17 00:00:00 2001
From: Xaver K <klemenschits@iue.tuwien.ac.at>
Date: Fri, 17 Apr 2020 19:27:16 +0200
Subject: [PATCH] Support for other standards than c11 (#3)
* Finished C89/C90/C95/C99 support. Version can only be switched in kernel or with magics. Might be worth having separate kernels for each standard.
* Added option to link maths library. On by default.
* Fixed empty input error. Now input loops until there is input with length > 0.
---
example-notebook.ipynb | 21 +++-----
jupyter_c_kernel/kernel.py | 12 ++++-
jupyter_c_kernel/resources/stdio_wrap.h | 72 ++++++++++++++++++++-----
3 files changed, 78 insertions(+), 27 deletions(-)
diff --git a/example-notebook.ipynb b/example-notebook.ipynb
index dcd2844..95b78b5 100644
--- a/example-notebook.ipynb
+++ b/example-notebook.ipynb
@@ -10,9 +10,7 @@
{
"cell_type": "code",
"execution_count": 1,
- "metadata": {
- "collapsed": false
- },
+ "metadata": {},
"outputs": [
{
"name": "stderr",
@@ -32,6 +30,7 @@
"\n",
"int main() {\n",
" printf(\"Hello world\\n\");\n",
+ " return 0;\n",
"}"
]
},
@@ -52,9 +51,7 @@
{
"cell_type": "code",
"execution_count": 2,
- "metadata": {
- "collapsed": false
- },
+ "metadata": {},
"outputs": [
{
"name": "stderr",
@@ -98,9 +95,7 @@
{
"cell_type": "code",
"execution_count": 3,
- "metadata": {
- "collapsed": false
- },
+ "metadata": {},
"outputs": [
{
"name": "stderr",
@@ -142,14 +137,14 @@
"kernelspec": {
"display_name": "C",
"language": "c",
- "name": "c_kernel"
+ "name": "c"
},
"language_info": {
- "file_extension": "c",
+ "file_extension": ".c",
"mimetype": "text/plain",
- "name": "c"
+ "name": "text/x-c++src"
}
},
"nbformat": 4,
- "nbformat_minor": 0
+ "nbformat_minor": 1
}
diff --git a/jupyter_c_kernel/kernel.py b/jupyter_c_kernel/kernel.py
index 99243fc..6194234 100644
--- a/jupyter_c_kernel/kernel.py
+++ b/jupyter_c_kernel/kernel.py
@@ -71,7 +71,9 @@ class RealTimeSubprocess(subprocess.Popen):
contents = contents.replace(self.__class__.inputRequest, '')
if(len(contents) > 0):
self._write_to_stdout(contents)
- readLine = self._read_from_stdin()
+ readLine = ""
+ while(len(readLine) == 0):
+ readLine = self._read_from_stdin()
# need to add newline since it is not captured by frontend
readLine += "\n"
self.stdin.write(readLine.encode())
@@ -104,6 +106,7 @@ class CKernel(Kernel):
super(CKernel, self).__init__(*args, **kwargs)
self._allow_stdin = True
self.readOnlyFileSystem = False
+ self.linkMaths = True # always link math library
self.wAll = True # show all warnings by default
self.wError = False # but keep comipiling for warnings
self.files = []
@@ -148,7 +151,12 @@ class CKernel(Kernel):
self._read_from_stdin)
def compile_with_gcc(self, source_filename, binary_filename, cflags=None, ldflags=None):
- cflags = ['-std=c11', '-fPIC', '-shared', '-rdynamic'] + cflags
+ # cflags = ['-std=c89', '-pedantic', '-fPIC', '-shared', '-rdynamic'] + cflags
+ # cflags = ['-std=iso9899:199409', '-pedantic', '-fPIC', '-shared', '-rdynamic'] + cflags
+ # cflags = ['-std=c99', '-pedantic', '-fPIC', '-shared', '-rdynamic'] + cflags
+ cflags = ['-std=c11', '-pedantic', '-fPIC', '-shared', '-rdynamic'] + cflags
+ if self.linkMaths:
+ cflags = cflags + ['-lm']
if self.wError:
cflags = cflags + ['-Werror']
if self.wAll:
diff --git a/jupyter_c_kernel/resources/stdio_wrap.h b/jupyter_c_kernel/resources/stdio_wrap.h
index 8a365d8..e079947 100644
--- a/jupyter_c_kernel/resources/stdio_wrap.h
+++ b/jupyter_c_kernel/resources/stdio_wrap.h
@@ -5,8 +5,20 @@
#include <stdarg.h>
#include <string.h>
+/* Figure out used C standard.
+ __STDC_VERSION__ is not always defined until C99.
+ If it is not defined, set standard to C89.
+ It is safest to set it by hand, to make sure */
+#ifdef __STDC_VERSION__
+#if __STDC_VERSION__ <= 199409L
+#define C89_SUPPORT
+#endif /* __STDC_VERSION__ <= 199409L */
+#else /* __STDC_VERSION__ */
+#define C89_SUPPORT
+#endif /* __STDC_VERSION__ */
+
/* Need input buffer to know whether we need another input request */
-char inputBuff[1<<10] = "";
+static char inputBuff[1<<10] = "";
/* read remaining input into buffer so it can be used in next call */
void readIntoBuffer() {
@@ -19,8 +31,8 @@ void readIntoBuffer() {
inputBuff[length] = '\0';
}
-/* Define the functions to overload the old ones */
-int scanf_wrap(const char *format, ...) {
+/* check whether input request is needed */
+char checkInputRequest() {
/* unget chars in buffer */
char doRequest = 1;
char leadingNewline = 1;
@@ -38,21 +50,49 @@ int scanf_wrap(const char *format, ...) {
}
}
+ return doRequest;
+}
+
+/* Define the functions to overload the old ones */
+
+/* Wrapping of scanf depends on standard */
+#ifdef C89_SUPPORT
+/* Need to define vscanf for c89.
+ TODO: This is a bit risky, since the underlying glibc does not
+ have to include this if it is old. If it does not, linking will fail.
+ The only safe way is reimplementing the whole function. */
+
+/* Read formatted input from stdin into argument list ARG.
+
+ This function is a possible cancellation point and therefore not
+ marked with __THROW. */
+extern int vscanf (const char *__restrict __format, _G_va_list __arg)
+ __attribute__ ((__format__ (__scanf__, 1, 0))) __wur;
+#endif /* C89_SUPPORT */
+
+int scanf_wrap(const char *format, ...) {
+ char doRequest = checkInputRequest();
+
if(doRequest) {
printf("<inputRequest>");
fflush(stdout);
}
- va_list arglist;
- va_start( arglist, format );
- int result = vscanf( format, arglist );
- va_end( arglist );
- /* Put the remaining input into the input buffer */
- readIntoBuffer();
+ {
+ va_list arglist;
+ int result;
+ va_start( arglist, format );
+ result = vscanf( format, arglist );
+ va_end( arglist );
- return result;
+ /* Put the remaining input into the input buffer */
+ readIntoBuffer();
+
+ return result;
+ }
}
+
int getchar_wrap(){
/* check if there is still something in the input buffer*/
char input = 0;
@@ -64,9 +104,10 @@ int getchar_wrap(){
input = getchar();
readIntoBuffer();
} else {
+ int i = 1;
+
input = inputBuff[0];
/* shift all chars one to the left */
- int i = 1;
for(; i < 100; ++i){
inputBuff[i-1] = inputBuff[i];
if(inputBuff[i] == '\0') {
@@ -79,8 +120,15 @@ int getchar_wrap(){
}
/* Replace all the necessary input functions
- Need double hashes in case there are no __VA_ARGS__*/
+ depending on the language version used */
+#ifndef C89_SUPPORT
+/* Need double hashes in case there are no __VA_ARGS__*/
#define scanf(format, ...) scanf_wrap(format, ##__VA_ARGS__)
+#else /* C89_SUPPORT */
+/* Since there are no variadic macros in C89, this is the only way
+ although it is horrible */
+#define scanf scanf_wrap
+#endif /* C89_SUPPORT */
#define getchar() getchar_wrap()