env: Add a function to convert pci addr to string

Convert an spdk_pci_addr to a string.

Change-Id: Idab0a16822cc37d7095d19f062dfca65356211e8
Signed-off-by: Ben Walker <benjamin.walker@intel.com>

include/spdk/env.h

@@ -237,6 +237,19 @@ int spdk_pci_addr_compare(const struct spdk_pci_addr *a1, const struct spdk_pci_
  */
 int spdk_pci_addr_parse(struct spdk_pci_addr *addr, const char *bdf);
 
+/**
+ * Convert a struct spdk_pci_addr to a string.
+ *
+ * \param bdf String into which a string will be output in the format
+ *            domain:bus:device.function. The string must be at least
+ *            14 characters in size.
+ * \param sz Size of bdf. Must be at least 14.
+ * \param addr PCI address input
+ *
+ * \return 0 on success, or a negated errno value on failure.
+ */
+int spdk_pci_addr_fmt(char *bdf, size_t sz, const struct spdk_pci_addr *addr);
+
 /**
  * Call a function with CPU affinity unset.
  *

lib/env_dpdk/pci.c

@@ -429,3 +429,19 @@ spdk_pci_addr_parse(struct spdk_pci_addr *addr, const char *bdf)
 
 	return 0;
 }
+
+int
+spdk_pci_addr_fmt(char *bdf, size_t sz, const struct spdk_pci_addr *addr)
+{
+	int rc;
+
+	rc = snprintf(bdf, sz, PCI_PRI_FMT,
+		      addr->domain, addr->bus,
+		      addr->dev, addr->func);
+
+	if (rc > 0 && (size_t)rc < sz) {
+		return 0;
+	}
+
+	return -1;
+}