libbpf: move libbpf_errstr() into libbpf_utils.c

Get rid of str_err.{c,h} by moving implementation of libbpf_errstr()
into libbpf_utils.c and declarations into libbpf_internal.h.

Signed-off-by: Andrii Nakryiko <[email protected]>

Author: anakryiko

tools/lib/bpf/Build

@@ -1,4 +1,4 @@
-libbpf-y := libbpf.o bpf.o nlattr.o btf.o libbpf_utils.o str_error.o \
+libbpf-y := libbpf.o bpf.o nlattr.o btf.o libbpf_utils.o \
 	    netlink.o bpf_prog_linfo.o libbpf_probes.o hashmap.o \
 	    btf_dump.o ringbuf.o strset.o linker.o gen_loader.o relo_core.o \
 	    usdt.o zip.o elf.o features.o btf_iter.o btf_relocate.o

tools/lib/bpf/btf.c

@@ -23,7 +23,6 @@
 #include "libbpf_internal.h"
 #include "hashmap.h"
 #include "strset.h"
-#include "str_error.h"
 
 #define BTF_MAX_NR_TYPES 0x7fffffffU
 #define BTF_MAX_STR_OFFSET 0x7fffffffU

tools/lib/bpf/btf_dump.c

@@ -21,7 +21,6 @@
 #include "hashmap.h"
 #include "libbpf.h"
 #include "libbpf_internal.h"
-#include "str_error.h"
 
 static const char PREFIXES[] = "\t\t\t\t\t\t\t\t\t\t\t\t\t";
 static const size_t PREFIX_CNT = sizeof(PREFIXES) - 1;

tools/lib/bpf/elf.c

@@ -9,7 +9,6 @@
 #include <linux/kernel.h>
 
 #include "libbpf_internal.h"
-#include "str_error.h"
 
 /* A SHT_GNU_versym section holds 16-bit words. This bit is set if
  * the symbol is hidden and can only be seen when referenced using an

tools/lib/bpf/features.c

@@ -6,7 +6,6 @@
 #include "libbpf.h"
 #include "libbpf_common.h"
 #include "libbpf_internal.h"
-#include "str_error.h"
 
 static inline __u64 ptr_to_u64(const void *ptr)
 {

tools/lib/bpf/gen_loader.c

@@ -4,6 +4,7 @@
 #include <stdlib.h>
 #include <string.h>
 #include <errno.h>
+#include <asm/byteorder.h>
 #include <linux/filter.h>
 #include <sys/param.h>
 #include "btf.h"
@@ -13,8 +14,6 @@
 #include "hashmap.h"
 #include "bpf_gen_internal.h"
 #include "skel_internal.h"
-#include <asm/byteorder.h>
-#include "str_error.h"
 
 #define MAX_USED_MAPS	64
 #define MAX_USED_PROGS	32

tools/lib/bpf/libbpf.c

@@ -51,7 +51,6 @@
 #include "libbpf.h"
 #include "bpf.h"
 #include "btf.h"
-#include "str_error.h"
 #include "libbpf_internal.h"
 #include "hashmap.h"
 #include "bpf_gen_internal.h"

tools/lib/bpf/libbpf_internal.h

@@ -172,6 +172,16 @@ do {				\
 #define pr_info(fmt, ...)	__pr(LIBBPF_INFO, fmt, ##__VA_ARGS__)
 #define pr_debug(fmt, ...)	__pr(LIBBPF_DEBUG, fmt, ##__VA_ARGS__)
 
+/**
+ * @brief **libbpf_errstr()** returns string corresponding to numeric errno
+ * @param err negative numeric errno
+ * @return pointer to string representation of the errno, that is invalidated
+ * upon the next call.
+ */
+const char *libbpf_errstr(int err);
+
+#define errstr(err) libbpf_errstr(err)
+
 #ifndef __has_builtin
 #define __has_builtin(x) 0
 #endif

tools/lib/bpf/libbpf_utils.c

@@ -10,10 +10,15 @@
 #undef _GNU_SOURCE
 #include <stdio.h>
 #include <string.h>
+#include <errno.h>
 
 #include "libbpf.h"
 #include "libbpf_internal.h"
 
+#ifndef ENOTSUPP
+#define ENOTSUPP	524
+#endif
+
 /* make sure libbpf doesn't use kernel-only integer typedefs */
 #pragma GCC poison u8 u16 u32 u64 s8 s16 s32 s64
 
@@ -73,3 +78,70 @@ int libbpf_strerror(int err, char *buf, size_t size)
 		return libbpf_err(-ERANGE);
 	return libbpf_err(-ENOENT);
 }
+
+const char *libbpf_errstr(int err)
+{
+	static __thread char buf[12];
+
+	if (err > 0)
+		err = -err;
+
+	switch (err) {
+	case -E2BIG:		return "-E2BIG";
+	case -EACCES:		return "-EACCES";
+	case -EADDRINUSE:	return "-EADDRINUSE";
+	case -EADDRNOTAVAIL:	return "-EADDRNOTAVAIL";
+	case -EAGAIN:		return "-EAGAIN";
+	case -EALREADY:		return "-EALREADY";
+	case -EBADF:		return "-EBADF";
+	case -EBADFD:		return "-EBADFD";
+	case -EBUSY:		return "-EBUSY";
+	case -ECANCELED:	return "-ECANCELED";
+	case -ECHILD:		return "-ECHILD";
+	case -EDEADLK:		return "-EDEADLK";
+	case -EDOM:		return "-EDOM";
+	case -EEXIST:		return "-EEXIST";
+	case -EFAULT:		return "-EFAULT";
+	case -EFBIG:		return "-EFBIG";
+	case -EILSEQ:		return "-EILSEQ";
+	case -EINPROGRESS:	return "-EINPROGRESS";
+	case -EINTR:		return "-EINTR";
+	case -EINVAL:		return "-EINVAL";
+	case -EIO:		return "-EIO";
+	case -EISDIR:		return "-EISDIR";
+	case -ELOOP:		return "-ELOOP";
+	case -EMFILE:		return "-EMFILE";
+	case -EMLINK:		return "-EMLINK";
+	case -EMSGSIZE:		return "-EMSGSIZE";
+	case -ENAMETOOLONG:	return "-ENAMETOOLONG";
+	case -ENFILE:		return "-ENFILE";
+	case -ENODATA:		return "-ENODATA";
+	case -ENODEV:		return "-ENODEV";
+	case -ENOENT:		return "-ENOENT";
+	case -ENOEXEC:		return "-ENOEXEC";
+	case -ENOLINK:		return "-ENOLINK";
+	case -ENOMEM:		return "-ENOMEM";
+	case -ENOSPC:		return "-ENOSPC";
+	case -ENOTBLK:		return "-ENOTBLK";
+	case -ENOTDIR:		return "-ENOTDIR";
+	case -ENOTSUPP:		return "-ENOTSUPP";
+	case -ENOTTY:		return "-ENOTTY";
+	case -ENXIO:		return "-ENXIO";
+	case -EOPNOTSUPP:	return "-EOPNOTSUPP";
+	case -EOVERFLOW:	return "-EOVERFLOW";
+	case -EPERM:		return "-EPERM";
+	case -EPIPE:		return "-EPIPE";
+	case -EPROTO:		return "-EPROTO";
+	case -EPROTONOSUPPORT:	return "-EPROTONOSUPPORT";
+	case -ERANGE:		return "-ERANGE";
+	case -EROFS:		return "-EROFS";
+	case -ESPIPE:		return "-ESPIPE";
+	case -ESRCH:		return "-ESRCH";
+	case -ETXTBSY:		return "-ETXTBSY";
+	case -EUCLEAN:		return "-EUCLEAN";
+	case -EXDEV:		return "-EXDEV";
+	default:
+		snprintf(buf, sizeof(buf), "%d", err);
+		return buf;
+	}
+}

tools/lib/bpf/linker.c

@@ -25,7 +25,6 @@
 #include "btf.h"
 #include "libbpf_internal.h"
 #include "strset.h"
-#include "str_error.h"
 
 #define BTF_EXTERN_SEC ".extern"