Fuzzing support via AFL

.gitignore

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+fuzzing/findings
+fuzzing/inihfuzz

fuzzing/build.sh

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+#!/usr/bin/env bash
+../../afl-2.52b/afl-gcc inihfuzz.c ../ini.c -o inihfuzz

fuzzing/fuzz.sh

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+#!/usr/bin/env bash
+../../afl-2.52b/afl-fuzz -i testcases -o findings -- ./inihfuzz @@

fuzzing/inihfuzz.c

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+/* This is a slightly tweaked copy of tests/unittest.c for fuzzing */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include "../ini.h"
+
+int User;
+char Prev_section[50];
+
+int dumper(void* user, const char* section, const char* name,
+           const char* value)
+{
+    User = *((int*)user);
+    if (!name || strcmp(section, Prev_section)) {
+        printf("... [%s]\n", section);
+        strncpy(Prev_section, section, sizeof(Prev_section));
+        Prev_section[sizeof(Prev_section) - 1] = '\0';
+    }
+    if (!name) {
+        return 1;
+    }
+
+    printf("... %s%s%s;\n", name, value ? "=" : "", value ? value : "");
+
+    if (!value) {
+        // Happens when INI_ALLOW_NO_VALUE=1 and line has no value (no '=' or ':')
+        return 1;
+    }
+
+    return strcmp(name, "user")==0 && strcmp(value, "parse_error")==0 ? 0 : 1;
+}
+
+void parse(const char* fname) {
+    static int u = 100;
+    int e;
+
+    *Prev_section = '\0';
+    e = ini_parse(fname, dumper, &u);
+    printf("%s: e=%d user=%d\n", fname, e, User);
+    u++;
+}
+
+int main(int argc, char **argv)
+{
+    if (argc < 2) {
+        printf("usage: inihfuzz file.ini\n");
+        return 1;
+    }
+    parse(argv[1]);
+    return 0;
+}

fuzzing/testcases/case1.ini

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+; comment
+
+[foo] ; section
+bar=1 ; name=value
+
+[bar]
+name = Bob
+age: 42