bpo-42827: Fix crash on SyntaxError in multiline expressions (GH-24140)
When trying to extract the error line for the error message there
are two distinct cases:
1. The input comes from a file, which means that we can extract the
error line by using `PyErr_ProgramTextObject` and which we already
do.
2. The input does not come from a file, at which point we need to get
the source code from the tokenizer:
* If the tokenizer's current line number is the same with the line
of the error, we get the line from `tok->buf` and we're ready.
* Else, we can extract the error line from the source code in the
following two ways:
* If the input comes from a string we have all the input
in `tok->str` and we can extract the error line from it.
* If the input comes from stdin, i.e. the interactive prompt, we
do not have access to the previous line. That's why a new
field `tok->stdin_content` is added which holds the whole input for the
current (multiline) statement or expression. We can then extract the
error line from `tok->stdin_content` like we do in the string case above.
Co-authored-by: Pablo Galindo <Pablogsal@gmail.com>diff --git a/Parser/tokenizer.c b/Parser/tokenizer.c
index 96539bd..62cd296 100644
--- a/Parser/tokenizer.c
+++ b/Parser/tokenizer.c
@@ -81,6 +81,7 @@ tok_new(void)
tok->decoding_readline = NULL;
tok->decoding_buffer = NULL;
tok->type_comments = 0;
+ tok->stdin_content = NULL;
tok->async_hacks = 0;
tok->async_def = 0;
@@ -816,6 +817,8 @@ PyTokenizer_Free(struct tok_state *tok)
PyMem_Free(tok->buf);
if (tok->input)
PyMem_Free(tok->input);
+ if (tok->stdin_content)
+ PyMem_Free(tok->stdin_content);
PyMem_Free(tok);
}
@@ -856,6 +859,24 @@ tok_nextc(struct tok_state *tok)
if (translated == NULL)
return EOF;
newtok = translated;
+ if (tok->stdin_content == NULL) {
+ tok->stdin_content = PyMem_Malloc(strlen(translated) + 1);
+ if (tok->stdin_content == NULL) {
+ tok->done = E_NOMEM;
+ return EOF;
+ }
+ sprintf(tok->stdin_content, "%s", translated);
+ }
+ else {
+ char *new_str = PyMem_Malloc(strlen(tok->stdin_content) + strlen(translated) + 1);
+ if (new_str == NULL) {
+ tok->done = E_NOMEM;
+ return EOF;
+ }
+ sprintf(new_str, "%s%s", tok->stdin_content, translated);
+ PyMem_Free(tok->stdin_content);
+ tok->stdin_content = new_str;
+ }
}
if (tok->encoding && newtok && *newtok) {
/* Recode to UTF-8 */