tools/testing/selftests/bpf/prog_tests/snprintf.c
Source file repositories/reference/linux-study-clean/tools/testing/selftests/bpf/prog_tests/snprintf.c
File Facts
- System
- Linux kernel
- Corpus path
tools/testing/selftests/bpf/prog_tests/snprintf.c- Extension
.c- Size
- 4194 bytes
- Lines
- 131
- Domain
- Support Tooling And Documentation
- Bucket
- tools
- Inferred role
- Support Tooling And Documentation: implementation source
- Status
- source implementation candidate
Why This File Exists
Repository support layer: documentation, build tooling, samples, user-space helper tools, generated initramfs support, licenses, and validation utilities.
- Repository support layer: documentation, build tooling, samples, user-space helper tools, generated initramfs support, licenses, and validation utilities.
- Defines or uses C structs; map object ownership, embedded links, reference counts, and lock ownership.
Dependency Surface
test_progs.htest_snprintf.skel.htest_snprintf_single.skel.h
Detected Declarations
function test_snprintf_positivefunction load_single_snprintffunction test_snprintf_negativefunction test_snprintf
Annotated Snippet
// SPDX-License-Identifier: GPL-2.0
/* Copyright (c) 2021 Google LLC. */
#include <test_progs.h>
#include "test_snprintf.skel.h"
#include "test_snprintf_single.skel.h"
#define EXP_NUM_OUT "-8 9 96 -424242 1337 DABBAD00"
#define EXP_NUM_RET sizeof(EXP_NUM_OUT)
#define EXP_IP_OUT "127.000.000.001 0000:0000:0000:0000:0000:0000:0000:0001"
#define EXP_IP_RET sizeof(EXP_IP_OUT)
/* The third specifier, %pB, depends on compiler inlining so don't check it */
#define EXP_SYM_OUT "schedule schedule+0x0/"
#define MIN_SYM_RET sizeof(EXP_SYM_OUT)
/* The third specifier, %p, is a hashed pointer which changes on every reboot */
#define EXP_ADDR_OUT "0000000000000000 ffff00000add4e55 "
#define EXP_ADDR_RET sizeof(EXP_ADDR_OUT "unknownhashedptr")
#define EXP_STR_OUT "str1 a b c d e longstr"
#define EXP_STR_RET sizeof(EXP_STR_OUT)
#define EXP_OVER_OUT "%over"
#define EXP_OVER_RET 10
#define EXP_PAD_OUT " 4 000"
#define EXP_PAD_RET 900007
#define EXP_NO_ARG_OUT "simple case"
#define EXP_NO_ARG_RET 12
#define EXP_NO_BUF_RET 29
static void test_snprintf_positive(void)
{
char exp_addr_out[] = EXP_ADDR_OUT;
char exp_sym_out[] = EXP_SYM_OUT;
struct test_snprintf *skel;
skel = test_snprintf__open_and_load();
if (!ASSERT_OK_PTR(skel, "skel_open"))
return;
skel->bss->pid = getpid();
if (!ASSERT_OK(test_snprintf__attach(skel), "skel_attach"))
goto cleanup;
/* trigger tracepoint */
usleep(1);
ASSERT_STREQ(skel->bss->num_out, EXP_NUM_OUT, "num_out");
ASSERT_EQ(skel->bss->num_ret, EXP_NUM_RET, "num_ret");
ASSERT_STREQ(skel->bss->ip_out, EXP_IP_OUT, "ip_out");
ASSERT_EQ(skel->bss->ip_ret, EXP_IP_RET, "ip_ret");
ASSERT_OK(memcmp(skel->bss->sym_out, exp_sym_out,
sizeof(exp_sym_out) - 1), "sym_out");
ASSERT_LT(MIN_SYM_RET, skel->bss->sym_ret, "sym_ret");
ASSERT_OK(memcmp(skel->bss->addr_out, exp_addr_out,
sizeof(exp_addr_out) - 1), "addr_out");
ASSERT_EQ(skel->bss->addr_ret, EXP_ADDR_RET, "addr_ret");
ASSERT_STREQ(skel->bss->str_out, EXP_STR_OUT, "str_out");
ASSERT_EQ(skel->bss->str_ret, EXP_STR_RET, "str_ret");
ASSERT_STREQ(skel->bss->over_out, EXP_OVER_OUT, "over_out");
ASSERT_EQ(skel->bss->over_ret, EXP_OVER_RET, "over_ret");
ASSERT_STREQ(skel->bss->pad_out, EXP_PAD_OUT, "pad_out");
ASSERT_EQ(skel->bss->pad_ret, EXP_PAD_RET, "pad_ret");
ASSERT_STREQ(skel->bss->noarg_out, EXP_NO_ARG_OUT, "no_arg_out");
ASSERT_EQ(skel->bss->noarg_ret, EXP_NO_ARG_RET, "no_arg_ret");
ASSERT_EQ(skel->bss->nobuf_ret, EXP_NO_BUF_RET, "no_buf_ret");
cleanup:
test_snprintf__destroy(skel);
}
/* Loads an eBPF object calling bpf_snprintf with up to 10 characters of fmt */
static int load_single_snprintf(char *fmt)
{
struct test_snprintf_single *skel;
int ret;
Annotation
- Immediate include surface: `test_progs.h`, `test_snprintf.skel.h`, `test_snprintf_single.skel.h`.
- Detected declarations: `function test_snprintf_positive`, `function load_single_snprintf`, `function test_snprintf_negative`, `function test_snprintf`.
- Atlas domain: Support Tooling And Documentation / tools.
- Implementation status: source implementation candidate.
Implementation Notes
- This generated page is the file-by-file coverage layer; curated subsystem chapters should link here when they synthesize a multi-file control flow.
- Core OS pages should be promoted from atlas-only to deep-reviewed when they explain data structures, invariants, locking, lifecycle, and C implementation snippets.
- Driver-family pages are intentionally pattern-oriented unless they are part of the selected PCIe/NVMe representative device path.