Add _c versions of functions that otherwise return static buffers

We have a habit of returning static buffers from some functions,
particularly when generating some kind of string values.  This is
convenient in terms of memory management, but it comes at the expense
of not being thread-safe, and not allowing for two calls of the
related function within one printf() statement.

Let's introduce _c suffix versions of those functions where the
caller passes in a talloc context from which the output buffer shall
be allocated.

Change-Id: I8481c19b68ff67cfa22abb93c405ebcfcb0ab19b

1 files changed, 59 insertions, 0 deletions

diff --git a/src/gsm/gsm48.c b/src/gsm/gsm48.c
index a45d67bc..c2c19cfe 100644
--- a/src/gsm/gsm48.c
+++ b/src/gsm/gsm48.c
@@ -36,6 +36,7 @@
 #include <osmocom/core/byteswap.h>
 #include <osmocom/core/bit16gen.h>
 #include <osmocom/core/bit32gen.h>
+#include <osmocom/core/talloc.h>
 #include <osmocom/gsm/tlv.h>
 #include <osmocom/gsm/gsm48.h>
 #include <osmocom/gsm/gsm0502.h>
@@ -206,6 +207,19 @@ const char *osmo_rai_name(const struct gprs_ra_id *rai)
 	return osmo_rai_name_buf(buf, sizeof(buf), rai);
 }
 
+/*! Return MCC-MNC-LAC-RAC as string, in dynamically-allocated output buffer.
+ * \param[in] ctx talloc context from which to allocate output buffer
+ * \param[in] rai  RAI to encode.
+ * \returns string representation in dynamically-allocated output buffer.
+ */
+char *osmo_rai_name_c(const void *ctx, const struct gprs_ra_id *rai)
+{
+	char *buf = talloc_size(ctx, 32);
+	if (!buf)
+		return NULL;
+	return osmo_rai_name_buf(buf, 32, rai);
+}
+
 /* FIXME: convert to value_string */
 static const char *cc_state_names[32] = {
 	"NULL",
@@ -492,6 +506,22 @@ const char *osmo_mi_name(const uint8_t *mi, uint8_t mi_len)
 	return osmo_mi_name_buf(mi_name, sizeof(mi_name), mi, mi_len);
 }
 
+/*! Return a human readable representation of a Mobile Identity in dynamically-allocated buffer.
+ * \param[in] ctx talloc context from which to allocate output buffer
+ * \param[in] mi  Mobile Identity buffer containing 3GPP TS 04.08 style MI type and data.
+ * \param[in] mi_len  Length of mi.
+ * \return A string like "IMSI-1234567", "TMSI-0x1234ABCD" or "unknown", "TMSI-invalid" in a
+ * 	   dynamically-allocated output buffer.
+ */
+char *osmo_mi_name_c(const void *ctx, const uint8_t *mi, uint8_t mi_len)
+{
+	size_t buf_len = 10 + GSM48_MI_SIZE + 1;
+	char *mi_name = talloc_size(ctx, buf_len);
+	if (!mi_name)
+		return NULL;
+	return osmo_mi_name_buf(mi_name, buf_len, mi, mi_len);
+}
+
 /*! Checks is particular message is cipherable in A/Gb mode according to
  *         3GPP TS 24.008 § 4.7.1.2
  *  \param[in] hdr Message header
@@ -1124,6 +1154,22 @@ const char *gsm48_pdisc_msgtype_name(uint8_t pdisc, uint8_t msg_type)
 	return gsm48_pdisc_msgtype_name_buf(namebuf, sizeof(namebuf), pdisc, msg_type);
 }
 
+/*! Compose a string naming the message type for given protocol, in a dynamically-allocated buffer.
+ * If the message type string is known, return the message type name, otherwise
+ * return "<protocol discriminator name>:<message type in hex>".
+ * \param[in] ctx talloc context from which to allocate output buffer
+ * \param[in] pdisc protocol discriminator like GSM48_PDISC_MM
+ * \param[in] msg_type message type like GSM48_MT_MM_LOC_UPD_REQUEST
+ * \returns string representation in dynamically allocated output buffer.
+ */
+char *gsm48_pdisc_msgtype_name_c(const void *ctx, uint8_t pdisc, uint8_t msg_type)
+{
+	char *namebuf = talloc_size(ctx, 64);
+	if (!namebuf)
+		return NULL;
+	return gsm48_pdisc_msgtype_name_buf(namebuf, 64, pdisc, msg_type);
+}
+
 const struct value_string gsm48_reject_value_names[] = {
 	 { GSM48_REJECT_IMSI_UNKNOWN_IN_HLR, "IMSI_UNKNOWN_IN_HLR" },
 	 { GSM48_REJECT_ILLEGAL_MS, "ILLEGAL_MS" },
@@ -1261,6 +1307,19 @@ const char *osmo_gsm48_classmark_a5_name(const struct osmo_gsm48_classmark *cm)
 	return osmo_gsm48_classmark_a5_name_buf(buf, sizeof(buf), cm);
 }
 
+/*! Return a string representation of A5 cipher algorithms indicated by Classmark 1, 2 and 3.
+ * \param[in] ctx talloc context from which to allocate output buffer
+ * \param[in] cm  Classmarks.
+ * \returns string like "cm1{a5/1=supported} cm2{0x23= A5/2 A5/3} no-cm3" in dynamically-allocated
+ *          output buffer.
+ */
+char *osmo_gsm48_classmark_a5_name_c(const void *ctx, const struct osmo_gsm48_classmark *cm)
+{
+	char *buf = talloc_size(ctx, 128);
+	if (!buf)
+		return NULL;
+	return osmo_gsm48_classmark_a5_name_buf(buf, 128, cm);
+}
 
 /*! Overwrite dst with the Classmark information present in src.
  * Add an new Classmark and overwrite in dst what src has to offer, but where src has no Classmark information, leave