From 05e78fa5231acaea42b2ba01e8abaf7c26535678 Mon Sep 17 00:00:00 2001
From: olemorud <ole.kristian.morud@cern.ch>
Date: Tue, 25 Apr 2023 07:22:07 +0200
Subject: [PATCH] Add error handling for read_number and fix it

---
 Makefile    |  4 ++--
 src/main.c  |  2 +-
 src/parse.c | 14 ++++++++++++--
 3 files changed, 15 insertions(+), 5 deletions(-)

diff --git a/Makefile b/Makefile
index 1d55a35..0baf282 100644
--- a/Makefile
+++ b/Makefile
@@ -12,11 +12,11 @@ CC := gcc
 # -fsanitize={address,undefined}
 CFLAGS.gcc.debug := -Og -ggdb -fanalyzer -DBACKTRACE -rdynamic -fsanitize=address -fno-omit-frame-pointer
 CFLAGS.gcc.release := -O3 -g -march=native -DNDEBUG
-CFLAGS.gcc := ${CFLAGS.gcc.${BUILD}} -Iinclude -Wall -Wextra -Wpedantic -Werror -fstack-protector-all -std=gnu11
+CFLAGS.gcc := ${CFLAGS.gcc.${BUILD}} -Iinclude -Wall -Wextra -Wpedantic -Werror -Wno-strict-aliasing -fstack-protector-all -std=gnu11
 
 CFLAGS.clang.debug=-O0 -g3 -DBACKTRACE -rdynamic
 CFLAGS.clang.release=-O3 -g -march=native -DNDEBUG
-CFLAGS.clang=-Wextra -Wall -Wpedantic -Werror -fstack-protector-all ${CFLAGS.clang.${BUILD}}
+CFLAGS.clang=-Iinclude -Wall -Wextra -Wpedantic -Werror -Wno-strict-aliasing -fstack-protector-all ${CFLAGS.clang.${BUILD}}
 
 CFLAGS := ${CFLAGS.${COMPILER}}
 
diff --git a/src/main.c b/src/main.c
index a1c6453..08f3ad4 100644
--- a/src/main.c
+++ b/src/main.c
@@ -36,7 +36,7 @@ int main(int argc, char* argv[])
 
     struct json_value x = parse_json_value(fp);
 
-    print_json(x, 1);
+    // print_json(x, 1);
 
     json_value_delete(x);
 
diff --git a/src/parse.c b/src/parse.c
index baa2101..b5d50e1 100644
--- a/src/parse.c
+++ b/src/parse.c
@@ -106,6 +106,7 @@ struct json_value parse_json_value(FILE* fp)
 
     default:
         if (isdigit(c)) {
+            ungetc(c, fp);
             result.type = number;
             result.number = read_number(fp);
         } else {
@@ -364,9 +365,18 @@ bool read_boolean(FILE* fp)
 */
 double read_number(FILE* fp)
 {
-    double n;
+    static const unsigned long neg_nan = 0xFFFFFFFFFFFFFFFFULL;
+    double n = *(double*)&neg_nan;
 
-    fscanf(fp, "%lf", &n);
+    int n_read = fscanf(fp, "%lf", &n);
+
+    /* try to read as long instead */
+    if (n_read == 0) {
+        err_ctx(UNEXPECTED_CHAR, fp, "(%s) number expected, found %lf", __func__, n);
+    }
+
+    if (n_read == EOF)
+        err_ctx(EARLY_EOF, fp, "(%s) unexpected EOF", __func__);
 
     return n;
 }