Keep the colleague's microbu-esp32c5 tree in this repository

obu-firmware builds against vanetza-idf from microbu-esp32c5/external, but
that tree was gitignored, so a clone of this repository could not build the
firmware it ships. It is now committed here as ordinary files in its own
folder, microbu-esp32c5/: the colleague's commit cf4b99f plus the V2X2MAP
bridge's signature verification (--trust) used on the bench. Nothing is
fetched from or pushed to the colleague's repository; this repository and
its remotes carry everything. The folder's own .gitignore keeps build output,
downloaded components and private key material out, as it did there; the
committed file set is identical to that repository's tracked files.

The ESP32-C5 is still flashed from obu-firmware/, which only takes
vanetza-idf from microbu-esp32c5/, so the two stay separate folders.
FLASHING.md says how to take a newer version of the colleague's tree (copy
it over the folder, rebuild, test, commit).

microbu-esp32c5/external/vanetza-idf/vanetza/asn1/support/NativeReal.c

@@ -0,0 +1,253 @@
+/*-
+ * Copyright (c) 2004-2017 Lev Walkin <vlm@lionet.info>. All rights reserved.
+ * Redistribution and modifications are permitted subject to BSD license.
+ */
+/*
+ * Read the NativeReal.h for the explanation wrt. differences between
+ * REAL and NativeReal.
+ * Basically, both are decoders and encoders of ASN.1 REAL type, but this
+ * implementation deals with the standard (machine-specific) representation
+ * of them instead of using the platform-independent buffer.
+ */
+#include "asn_internal.h"
+#include "NativeReal.h"
+#include "REAL.h"
+#include <math.h>
+
+#if defined(__clang__)
+/*
+ * isnan() is defined using generic selections and won't compile in
+ * strict C89 mode because of too fancy system's standard library.
+ * However, prior to C11 the math had a perfectly working isnan()
+ * in the math library.
+ * Disable generic selection warning so we can test C89 mode with newer libc.
+ */
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wc11-extensions"
+static int asn_isnan(double d) {
+    return isnan(d);
+}
+#pragma clang diagnostic pop
+#else
+#define asn_isnan(v)    isnan(v)
+#endif  /* generic selections */
+
+/*
+ * NativeReal basic type description.
+ */
+static const ber_tlv_tag_t asn_DEF_NativeReal_tags[] = {
+    (ASN_TAG_CLASS_UNIVERSAL | (9 << 2))
+};
+asn_TYPE_operation_t asn_OP_NativeReal = {
+    NativeReal_free,
+#if !defined(ASN_DISABLE_PRINT_SUPPORT)
+    NativeReal_print,
+#else
+    0,
+#endif  /* !defined(ASN_DISABLE_PRINT_SUPPORT) */
+    NativeReal_compare,
+    NativeReal_copy,
+#if !defined(ASN_DISABLE_BER_SUPPORT)
+    NativeReal_decode_ber,
+    NativeReal_encode_der,
+#else
+    0,
+    0,
+#endif  /* !defined(ASN_DISABLE_BER_SUPPORT) */
+#if !defined(ASN_DISABLE_XER_SUPPORT)
+    NativeReal_decode_xer,
+    NativeReal_encode_xer,
+#else
+    0,
+    0,
+#endif  /* !defined(ASN_DISABLE_XER_SUPPORT) */
+#if !defined(ASN_DISABLE_JER_SUPPORT)
+    NativeReal_decode_jer,
+    NativeReal_encode_jer,
+#else
+    0,
+    0,
+#endif  /* !defined(ASN_DISABLE_JER_SUPPORT) */
+#if !defined(ASN_DISABLE_OER_SUPPORT)
+    NativeReal_decode_oer,
+    NativeReal_encode_oer,
+#else
+    0,
+    0,
+#endif  /* !defined(ASN_DISABLE_OER_SUPPORT) */
+#if !defined(ASN_DISABLE_UPER_SUPPORT)
+    NativeReal_decode_uper,
+    NativeReal_encode_uper,
+#else
+    0,
+    0,
+#endif  /* !defined(ASN_DISABLE_UPER_SUPPORT) */
+#if !defined(ASN_DISABLE_APER_SUPPORT)
+    NativeReal_decode_aper,
+    NativeReal_encode_aper,
+#else
+    0,
+    0,
+#endif  /* !defined(ASN_DISABLE_APER_SUPPORT) */
+#if !defined(ASN_DISABLE_RFILL_SUPPORT)
+    NativeReal_random_fill,
+#else
+    0,
+#endif  /* !defined(ASN_DISABLE_RFILL_SUPPORT) */
+    0  /* Use generic outmost tag fetcher */
+};
+asn_TYPE_descriptor_t asn_DEF_NativeReal = {
+    "REAL",  /* The ASN.1 type is still REAL */
+    "REAL",
+    &asn_OP_NativeReal,
+    asn_DEF_NativeReal_tags,
+    sizeof(asn_DEF_NativeReal_tags) / sizeof(asn_DEF_NativeReal_tags[0]),
+    asn_DEF_NativeReal_tags,	/* Same as above */
+    sizeof(asn_DEF_NativeReal_tags) / sizeof(asn_DEF_NativeReal_tags[0]),
+    {
+#if !defined(ASN_DISABLE_OER_SUPPORT)
+        0,
+#endif  /* !defined(ASN_DISABLE_OER_SUPPORT) */
+#if !defined(ASN_DISABLE_UPER_SUPPORT) || !defined(ASN_DISABLE_APER_SUPPORT)
+        0,
+#endif  /* !defined(ASN_DISABLE_UPER_SUPPORT) || !defined(ASN_DISABLE_APER_SUPPORT) */
+#if !defined(ASN_DISABLE_JER_SUPPORT)
+        0,
+#endif  /* !defined(ASN_DISABLE_JER_SUPPORT) */
+        asn_generic_no_constraint
+    },
+    0, 0,  /* No members */
+    0  /* No specifics */
+};
+
+int
+NativeReal_compare(const asn_TYPE_descriptor_t *td, const void *aptr,
+                   const void *bptr) {
+
+    if(aptr && bptr) {
+        double a = NativeReal__get_double(td, aptr);
+        double b = NativeReal__get_double(td, bptr);
+
+        /* NaN sorted above everything else */
+        if(asn_isnan(a)) {
+            if(asn_isnan(b)) {
+                return 0;
+            } else {
+                return -1;
+            }
+        } else if(asn_isnan(b)) {
+            return 1;
+        }
+        /* Value comparison. */
+        if(a < b) {
+            return -1;
+        } else if(a > b) {
+            return 1;
+        } else {
+            return 0;
+        }
+    } else if(!aptr) {
+        return -1;
+    } else {
+        return 1;
+    }
+}
+
+int
+NativeReal_copy(const asn_TYPE_descriptor_t *td, void **aptr,
+                   const void *bptr) {
+    size_t float_size = NativeReal__float_size(td);
+    void *a = *aptr;
+    const void *b = bptr;
+
+    if(!b) {
+        if(a) {
+            FREEMEM(a);
+            *aptr = 0;
+        }
+        return 0;
+    }
+
+    if(!a) {
+        a = *aptr = MALLOC(float_size);
+        if(!a) return -1;
+    }
+
+    if(float_size == sizeof(float)) {
+        *(float *)a = *(const float *)b;
+    } else {
+        *(double *)a = *(const double *)b;
+    }
+
+    return 0;
+}
+
+void
+NativeReal_free(const asn_TYPE_descriptor_t *td, void *ptr,
+                enum asn_struct_free_method method) {
+    if(!td || !ptr)
+		return;
+
+	ASN_DEBUG("Freeing %s as REAL (%d, %p, Native)",
+		td->name, method, ptr);
+
+    switch(method) {
+    case ASFM_FREE_EVERYTHING:
+        FREEMEM(ptr);
+        break;
+    case ASFM_FREE_UNDERLYING:
+        break;
+    case ASFM_FREE_UNDERLYING_AND_RESET: {
+        const asn_NativeReal_specifics_t *specs;
+        size_t float_size;
+        specs = (const asn_NativeReal_specifics_t *)td->specifics;
+        float_size = specs ? specs->float_size : sizeof(double);
+        memset(ptr, 0, float_size);
+    } break;
+    }
+}
+
+/*
+ * Local helper functions.
+ */
+
+size_t
+NativeReal__float_size(const asn_TYPE_descriptor_t *td) {
+    const asn_NativeReal_specifics_t *specs =
+        (const asn_NativeReal_specifics_t *)td->specifics;
+    return specs ? specs->float_size : sizeof(double);
+}
+
+double
+NativeReal__get_double(const asn_TYPE_descriptor_t *td, const void *ptr) {
+    size_t float_size = NativeReal__float_size(td);
+    if(float_size == sizeof(float)) {
+        return *(const float *)ptr;
+    } else {
+        return *(const double *)ptr;
+    }
+}
+
+ssize_t  /* Returns -1 or float size. */
+NativeReal__set(const asn_TYPE_descriptor_t *td, void **sptr, double d) {
+    size_t float_size = NativeReal__float_size(td);
+    void *native;
+
+    if(!(native = *sptr)) {
+        native = (*sptr = CALLOC(1, float_size));
+        if(!native) {
+            return -1;
+        }
+    }
+
+    if(float_size == sizeof(float)) {
+        if(asn_double2float(d, (float *)native)) {
+            return -1;
+        }
+    } else {
+        *(double *)native = d;
+    }
+
+    return float_size;
+}
+