Replace fmemopen.
A new implementation starting from the FreeBSD fmemopen rather than the
OpenBSD one we used to use.
The tests were arrived at by translating each sentence in
http://pubs.opengroup.org/onlinepubs/9699919799/functions/fmemopen.html,
plus http://man7.org/linux/man-pages/man3/fmemopen.3.html for historical
GNU bugs.
Bug: http://b/31304889
Test: ran tests
Change-Id: Id8b168c9ecde638e9cdedbc3b8a0982fc83c7048
diff --git a/tests/stdio_test.cpp b/tests/stdio_test.cpp
index da70d21..1f27c83 100644
--- a/tests/stdio_test.cpp
+++ b/tests/stdio_test.cpp
@@ -27,6 +27,7 @@
#include <wchar.h>
#include <locale.h>
+#include <string>
#include <vector>
#include "BionicDeathTest.h"
@@ -41,6 +42,8 @@
#define STDIO_DEATHTEST stdio_DeathTest
#endif
+using namespace std::string_literals;
+
class stdio_DeathTest : public BionicDeathTest {};
class stdio_nofortify_DeathTest : public BionicDeathTest {};
@@ -923,7 +926,7 @@
ASSERT_EQ(WEOF, fgetwc(fp));
ASSERT_EQ(EILSEQ, errno);
- fclose(fp);
+ ASSERT_EQ(0, fclose(fp));
}
TEST(STDIO_TEST, fmemopen) {
@@ -934,32 +937,410 @@
ASSERT_NE(EOF, fputs("abc>\n", fp));
fflush(fp);
+ // We wrote to the buffer...
ASSERT_STREQ("<abc>\n", buf);
+ // And can read back from the file.
AssertFileIs(fp, "<abc>\n", true);
- fclose(fp);
+ ASSERT_EQ(0, fclose(fp));
}
-TEST(STDIO_TEST, KNOWN_FAILURE_ON_BIONIC(fmemopen_NULL)) {
+TEST(STDIO_TEST, fmemopen_nullptr) {
FILE* fp = fmemopen(nullptr, 128, "r+");
ASSERT_NE(EOF, fputs("xyz\n", fp));
AssertFileIs(fp, "xyz\n", true);
- fclose(fp);
+ ASSERT_EQ(0, fclose(fp));
}
-TEST(STDIO_TEST, fmemopen_EINVAL) {
+TEST(STDIO_TEST, fmemopen_trailing_NUL_byte) {
+ FILE* fp;
+ char buf[8];
+
+ // POSIX: "When a stream open for writing is flushed or closed, a null byte
+ // shall be written at the current position or at the end of the buffer,
+ // depending on the size of the contents."
+ memset(buf, 'x', sizeof(buf));
+ ASSERT_NE(nullptr, fp = fmemopen(buf, sizeof(buf), "w"));
+ // Even with nothing written (and not in truncate mode), we'll flush a NUL...
+ ASSERT_EQ(0, fflush(fp));
+ EXPECT_EQ("\0xxxxxxx"s, std::string(buf, buf + sizeof(buf)));
+ // Now write and check that the NUL moves along with our writes...
+ ASSERT_NE(EOF, fputs("hello", fp));
+ ASSERT_EQ(0, fflush(fp));
+ EXPECT_EQ("hello\0xx"s, std::string(buf, buf + sizeof(buf)));
+ ASSERT_NE(EOF, fputs("wo", fp));
+ ASSERT_EQ(0, fflush(fp));
+ EXPECT_EQ("hellowo\0"s, std::string(buf, buf + sizeof(buf)));
+ ASSERT_EQ(0, fclose(fp));
+
+ // "If a stream open for update is flushed or closed and the last write has
+ // advanced the current buffer size, a null byte shall be written at the end
+ // of the buffer if it fits."
+ memset(buf, 'x', sizeof(buf));
+ ASSERT_NE(nullptr, fp = fmemopen(buf, sizeof(buf), "r+"));
+ // Nothing written yet, so no advance...
+ ASSERT_EQ(0, fflush(fp));
+ EXPECT_EQ("xxxxxxxx"s, std::string(buf, buf + sizeof(buf)));
+ ASSERT_NE(EOF, fputs("hello", fp));
+ ASSERT_EQ(0, fclose(fp));
+}
+
+TEST(STDIO_TEST, fmemopen_size) {
+ FILE* fp;
char buf[16];
+ memset(buf, 'x', sizeof(buf));
- // Invalid size.
- errno = 0;
- ASSERT_EQ(nullptr, fmemopen(buf, 0, "r+"));
- ASSERT_EQ(EINVAL, errno);
+ // POSIX: "The stream shall also maintain the size of the current buffer
+ // contents; use of fseek() or fseeko() on the stream with SEEK_END shall
+ // seek relative to this size."
- // No '+' with NULL buffer.
+ // "For modes r and r+ the size shall be set to the value given by the size
+ // argument."
+ ASSERT_NE(nullptr, fp = fmemopen(buf, 16, "r"));
+ ASSERT_EQ(0, fseek(fp, 0, SEEK_END));
+ EXPECT_EQ(16, ftell(fp));
+ EXPECT_EQ(16, ftello(fp));
+ ASSERT_EQ(0, fseeko(fp, 0, SEEK_END));
+ EXPECT_EQ(16, ftell(fp));
+ EXPECT_EQ(16, ftello(fp));
+ ASSERT_EQ(0, fclose(fp));
+ ASSERT_NE(nullptr, fp = fmemopen(buf, 16, "r+"));
+ ASSERT_EQ(0, fseek(fp, 0, SEEK_END));
+ EXPECT_EQ(16, ftell(fp));
+ EXPECT_EQ(16, ftello(fp));
+ ASSERT_EQ(0, fseeko(fp, 0, SEEK_END));
+ EXPECT_EQ(16, ftell(fp));
+ EXPECT_EQ(16, ftello(fp));
+ ASSERT_EQ(0, fclose(fp));
+
+ // "For modes w and w+ the initial size shall be zero..."
+ ASSERT_NE(nullptr, fp = fmemopen(nullptr, 16, "w"));
+ ASSERT_EQ(0, fseek(fp, 0, SEEK_END));
+ EXPECT_EQ(0, ftell(fp));
+ EXPECT_EQ(0, ftello(fp));
+ ASSERT_EQ(0, fseeko(fp, 0, SEEK_END));
+ EXPECT_EQ(0, ftell(fp));
+ EXPECT_EQ(0, ftello(fp));
+ ASSERT_EQ(0, fclose(fp));
+ ASSERT_NE(nullptr, fp = fmemopen(nullptr, 16, "w+"));
+ ASSERT_EQ(0, fseek(fp, 0, SEEK_END));
+ EXPECT_EQ(0, ftell(fp));
+ EXPECT_EQ(0, ftello(fp));
+ ASSERT_EQ(0, fseeko(fp, 0, SEEK_END));
+ EXPECT_EQ(0, ftell(fp));
+ EXPECT_EQ(0, ftello(fp));
+ ASSERT_EQ(0, fclose(fp));
+
+ // "...and for modes a and a+ the initial size shall be:
+ // 1. Zero, if buf is a null pointer
+ ASSERT_NE(nullptr, fp = fmemopen(nullptr, 16, "a"));
+ ASSERT_EQ(0, fseek(fp, 0, SEEK_END));
+ EXPECT_EQ(0, ftell(fp));
+ EXPECT_EQ(0, ftello(fp));
+ ASSERT_EQ(0, fseeko(fp, 0, SEEK_END));
+ EXPECT_EQ(0, ftell(fp));
+ EXPECT_EQ(0, ftello(fp));
+ ASSERT_EQ(0, fclose(fp));
+ ASSERT_NE(nullptr, fp = fmemopen(nullptr, 16, "a+"));
+ ASSERT_EQ(0, fseek(fp, 0, SEEK_END));
+ EXPECT_EQ(0, ftell(fp));
+ EXPECT_EQ(0, ftello(fp));
+ ASSERT_EQ(0, fseeko(fp, 0, SEEK_END));
+ EXPECT_EQ(0, ftell(fp));
+ EXPECT_EQ(0, ftello(fp));
+ ASSERT_EQ(0, fclose(fp));
+
+ // 2. The position of the first null byte in the buffer, if one is found
+ memset(buf, 'x', sizeof(buf));
+ buf[3] = '\0';
+ ASSERT_NE(nullptr, fp = fmemopen(buf, 16, "a"));
+ ASSERT_EQ(0, fseek(fp, 0, SEEK_END));
+ EXPECT_EQ(3, ftell(fp));
+ EXPECT_EQ(3, ftello(fp));
+ ASSERT_EQ(0, fseeko(fp, 0, SEEK_END));
+ EXPECT_EQ(3, ftell(fp));
+ EXPECT_EQ(3, ftello(fp));
+ ASSERT_EQ(0, fclose(fp));
+ memset(buf, 'x', sizeof(buf));
+ buf[3] = '\0';
+ ASSERT_NE(nullptr, fp = fmemopen(buf, 16, "a+"));
+ ASSERT_EQ(0, fseek(fp, 0, SEEK_END));
+ EXPECT_EQ(3, ftell(fp));
+ EXPECT_EQ(3, ftello(fp));
+ ASSERT_EQ(0, fseeko(fp, 0, SEEK_END));
+ EXPECT_EQ(3, ftell(fp));
+ EXPECT_EQ(3, ftello(fp));
+ ASSERT_EQ(0, fclose(fp));
+
+ // 3. The value of the size argument, if buf is not a null pointer and no
+ // null byte is found.
+ memset(buf, 'x', sizeof(buf));
+ ASSERT_NE(nullptr, fp = fmemopen(buf, 16, "a"));
+ ASSERT_EQ(0, fseek(fp, 0, SEEK_END));
+ EXPECT_EQ(16, ftell(fp));
+ EXPECT_EQ(16, ftello(fp));
+ ASSERT_EQ(0, fseeko(fp, 0, SEEK_END));
+ EXPECT_EQ(16, ftell(fp));
+ EXPECT_EQ(16, ftello(fp));
+ ASSERT_EQ(0, fclose(fp));
+ memset(buf, 'x', sizeof(buf));
+ ASSERT_NE(nullptr, fp = fmemopen(buf, 16, "a+"));
+ ASSERT_EQ(0, fseek(fp, 0, SEEK_END));
+ EXPECT_EQ(16, ftell(fp));
+ EXPECT_EQ(16, ftello(fp));
+ ASSERT_EQ(0, fseeko(fp, 0, SEEK_END));
+ EXPECT_EQ(16, ftell(fp));
+ EXPECT_EQ(16, ftello(fp));
+ ASSERT_EQ(0, fclose(fp));
+}
+
+TEST(STDIO_TEST, fmemopen_SEEK_END) {
+ // fseek SEEK_END is relative to the current string length, not the buffer size.
+ FILE* fp;
+ char buf[8];
+ memset(buf, 'x', sizeof(buf));
+ strcpy(buf, "str");
+ ASSERT_NE(nullptr, fp = fmemopen(buf, sizeof(buf), "w+"));
+ ASSERT_NE(EOF, fputs("string", fp));
+ EXPECT_EQ(0, fseek(fp, 0, SEEK_END));
+ EXPECT_EQ(static_cast<long>(strlen("string")), ftell(fp));
+ EXPECT_EQ(static_cast<off_t>(strlen("string")), ftello(fp));
+ EXPECT_EQ(0, fclose(fp));
+
+ // glibc < 2.22 interpreted SEEK_END the wrong way round (subtracting rather
+ // than adding).
+ ASSERT_NE(nullptr, fp = fmemopen(buf, sizeof(buf), "w+"));
+ ASSERT_NE(EOF, fputs("54321", fp));
+ EXPECT_EQ(0, fseek(fp, -2, SEEK_END));
+ EXPECT_EQ('2', fgetc(fp));
+ EXPECT_EQ(0, fclose(fp));
+}
+
+TEST(STDIO_TEST, fmemopen_seek_invalid) {
+ char buf[8];
+ memset(buf, 'x', sizeof(buf));
+ FILE* fp = fmemopen(buf, sizeof(buf), "w");
+ ASSERT_TRUE(fp != nullptr);
+
+ // POSIX: "An attempt to seek ... to a negative position or to a position
+ // larger than the buffer size given in the size argument shall fail."
+ // (There's no mention of what errno should be set to, and glibc doesn't
+ // set errno in any of these cases.)
+ EXPECT_EQ(-1, fseek(fp, -2, SEEK_SET));
+ EXPECT_EQ(-1, fseeko(fp, -2, SEEK_SET));
+ EXPECT_EQ(-1, fseek(fp, sizeof(buf) + 1, SEEK_SET));
+ EXPECT_EQ(-1, fseeko(fp, sizeof(buf) + 1, SEEK_SET));
+}
+
+TEST(STDIO_TEST, fmemopen_read_EOF) {
+ // POSIX: "A read operation on the stream shall not advance the current
+ // buffer position beyond the current buffer size."
+ char buf[8];
+ memset(buf, 'x', sizeof(buf));
+ FILE* fp = fmemopen(buf, sizeof(buf), "r");
+ ASSERT_TRUE(fp != nullptr);
+ char buf2[BUFSIZ];
+ ASSERT_EQ(8U, fread(buf2, 1, sizeof(buf2), fp));
+ // POSIX: "Reaching the buffer size in a read operation shall count as
+ // end-of-file.
+ ASSERT_TRUE(feof(fp));
+ ASSERT_EQ(EOF, fgetc(fp));
+ ASSERT_EQ(0, fclose(fp));
+}
+
+TEST(STDIO_TEST, fmemopen_read_null_bytes) {
+ // POSIX: "Null bytes in the buffer shall have no special meaning for reads."
+ char buf[] = "h\0e\0l\0l\0o";
+ FILE* fp = fmemopen(buf, sizeof(buf), "r");
+ ASSERT_TRUE(fp != nullptr);
+ ASSERT_EQ('h', fgetc(fp));
+ ASSERT_EQ(0, fgetc(fp));
+ ASSERT_EQ('e', fgetc(fp));
+ ASSERT_EQ(0, fgetc(fp));
+ ASSERT_EQ('l', fgetc(fp));
+ ASSERT_EQ(0, fgetc(fp));
+ // POSIX: "The read operation shall start at the current buffer position of
+ // the stream."
+ char buf2[8];
+ memset(buf2, 'x', sizeof(buf2));
+ ASSERT_EQ(4U, fread(buf2, 1, sizeof(buf2), fp));
+ ASSERT_EQ('l', buf2[0]);
+ ASSERT_EQ(0, buf2[1]);
+ ASSERT_EQ('o', buf2[2]);
+ ASSERT_EQ(0, buf2[3]);
+ for (size_t i = 4; i < sizeof(buf2); ++i) ASSERT_EQ('x', buf2[i]) << i;
+ ASSERT_TRUE(feof(fp));
+ ASSERT_EQ(0, fclose(fp));
+}
+
+TEST(STDIO_TEST, fmemopen_write) {
+ FILE* fp;
+ char buf[8];
+
+ // POSIX: "A write operation shall start either at the current position of
+ // the stream (if mode has not specified 'a' as the first character)..."
+ memset(buf, 'x', sizeof(buf));
+ ASSERT_NE(nullptr, fp = fmemopen(buf, sizeof(buf), "r+"));
+ setbuf(fp, nullptr); // Turn off buffering so we can see what's happening as it happens.
+ ASSERT_EQ(0, fseek(fp, 2, SEEK_SET));
+ ASSERT_EQ(' ', fputc(' ', fp));
+ EXPECT_EQ("xx xxxxx", std::string(buf, buf + sizeof(buf)));
+ ASSERT_EQ(0, fclose(fp));
+
+ // "...or at the current size of the stream (if mode had 'a' as the first
+ // character)." (See the fmemopen_size test for what "size" means, but for
+ // mode "a", it's the first NUL byte.)
+ memset(buf, 'x', sizeof(buf));
+ buf[3] = '\0';
+ ASSERT_NE(nullptr, fp = fmemopen(buf, sizeof(buf), "a+"));
+ setbuf(fp, nullptr); // Turn off buffering so we can see what's happening as it happens.
+ ASSERT_EQ(' ', fputc(' ', fp));
+ EXPECT_EQ("xxx \0xxx"s, std::string(buf, buf + sizeof(buf)));
+ ASSERT_EQ(0, fclose(fp));
+
+ // "If the current position at the end of the write is larger than the
+ // current buffer size, the current buffer size shall be set to the current
+ // position." (See the fmemopen_size test for what "size" means, but to
+ // query it we SEEK_END with offset 0, and then ftell.)
+ memset(buf, 'x', sizeof(buf));
+ ASSERT_NE(nullptr, fp = fmemopen(buf, sizeof(buf), "w+"));
+ setbuf(fp, nullptr); // Turn off buffering so we can see what's happening as it happens.
+ ASSERT_EQ(0, fseek(fp, 0, SEEK_END));
+ EXPECT_EQ(0, ftell(fp));
+ ASSERT_EQ(' ', fputc(' ', fp));
+ ASSERT_EQ(0, fseek(fp, 0, SEEK_END));
+ EXPECT_EQ(1, ftell(fp));
+ ASSERT_NE(EOF, fputs("123", fp));
+ ASSERT_EQ(0, fseek(fp, 0, SEEK_END));
+ EXPECT_EQ(4, ftell(fp));
+ EXPECT_EQ(" 123\0xxx"s, std::string(buf, buf + sizeof(buf)));
+ ASSERT_EQ(0, fclose(fp));
+}
+
+TEST(STDIO_TEST, fmemopen_write_EOF) {
+ // POSIX: "A write operation on the stream shall not advance the current
+ // buffer size beyond the size given in the size argument."
+ FILE* fp;
+
+ // Scalar writes...
+ ASSERT_NE(nullptr, fp = fmemopen(nullptr, 4, "w"));
+ setbuf(fp, nullptr); // Turn off buffering so we can see what's happening as it happens.
+ ASSERT_EQ('x', fputc('x', fp));
+ ASSERT_EQ('x', fputc('x', fp));
+ ASSERT_EQ('x', fputc('x', fp));
+ ASSERT_EQ(EOF, fputc('x', fp)); // Only 3 fit because of the implicit NUL.
+ ASSERT_EQ(0, fclose(fp));
+
+ // Vector writes...
+ ASSERT_NE(nullptr, fp = fmemopen(nullptr, 4, "w"));
+ setbuf(fp, nullptr); // Turn off buffering so we can see what's happening as it happens.
+ ASSERT_EQ(3U, fwrite("xxxx", 1, 4, fp));
+ ASSERT_EQ(0, fclose(fp));
+}
+
+TEST(STDIO_TEST, fmemopen_initial_position) {
+ // POSIX: "The ... current position in the buffer ... shall be initially
+ // set to either the beginning of the buffer (for r and w modes) ..."
+ char buf[] = "hello\0world";
+ FILE* fp;
+ ASSERT_NE(nullptr, fp = fmemopen(buf, sizeof(buf), "r"));
+ EXPECT_EQ(0L, ftell(fp));
+ EXPECT_EQ(0, fclose(fp));
+ ASSERT_NE(nullptr, fp = fmemopen(buf, sizeof(buf), "w"));
+ EXPECT_EQ(0L, ftell(fp));
+ EXPECT_EQ(0, fclose(fp));
+ buf[0] = 'h'; // (Undo the effects of the above.)
+
+ // POSIX: "...or to the first null byte in the buffer (for a modes)."
+ ASSERT_NE(nullptr, fp = fmemopen(buf, sizeof(buf), "a"));
+ EXPECT_EQ(5L, ftell(fp));
+ EXPECT_EQ(0, fclose(fp));
+
+ // POSIX: "If no null byte is found in append mode, the initial position
+ // shall be set to one byte after the end of the buffer."
+ memset(buf, 'x', sizeof(buf));
+ ASSERT_NE(nullptr, fp = fmemopen(buf, sizeof(buf), "a"));
+ EXPECT_EQ(static_cast<long>(sizeof(buf)), ftell(fp));
+ EXPECT_EQ(0, fclose(fp));
+}
+
+TEST(STDIO_TEST, fmemopen_initial_position_allocated) {
+ // POSIX: "If buf is a null pointer, the initial position shall always be
+ // set to the beginning of the buffer."
+ FILE* fp = fmemopen(nullptr, 128, "a+");
+ ASSERT_TRUE(fp != nullptr);
+ EXPECT_EQ(0L, ftell(fp));
+ EXPECT_EQ(0L, fseek(fp, 0, SEEK_SET));
+ EXPECT_EQ(0, fclose(fp));
+}
+
+TEST(STDIO_TEST, fmemopen_zero_length) {
+ // POSIX says it's up to the implementation whether or not you can have a
+ // zero-length buffer (but "A future version of this standard may require
+ // support of zero-length buffer streams explicitly"). BSD and glibc < 2.22
+ // agreed that you couldn't, but glibc >= 2.22 allows it for consistency.
+ FILE* fp;
+ char buf[16];
+ ASSERT_NE(nullptr, fp = fmemopen(buf, 0, "r+"));
+ ASSERT_EQ(EOF, fgetc(fp));
+ ASSERT_TRUE(feof(fp));
+ ASSERT_EQ(0, fclose(fp));
+ ASSERT_NE(nullptr, fp = fmemopen(nullptr, 0, "r+"));
+ ASSERT_EQ(EOF, fgetc(fp));
+ ASSERT_TRUE(feof(fp));
+ ASSERT_EQ(0, fclose(fp));
+
+ ASSERT_NE(nullptr, fp = fmemopen(buf, 0, "w+"));
+ setbuf(fp, nullptr); // Turn off buffering so we can see what's happening as it happens.
+ ASSERT_EQ(EOF, fputc('x', fp));
+ ASSERT_EQ(0, fclose(fp));
+ ASSERT_NE(nullptr, fp = fmemopen(nullptr, 0, "w+"));
+ setbuf(fp, nullptr); // Turn off buffering so we can see what's happening as it happens.
+ ASSERT_EQ(EOF, fputc('x', fp));
+ ASSERT_EQ(0, fclose(fp));
+}
+
+TEST(STDIO_TEST, fmemopen_write_only_allocated) {
+ // POSIX says fmemopen "may fail if the mode argument does not include a '+'".
+ // BSD fails, glibc doesn't. We side with the more lenient.
+ FILE* fp;
+ ASSERT_NE(nullptr, fp = fmemopen(nullptr, 16, "r"));
+ ASSERT_EQ(0, fclose(fp));
+ ASSERT_NE(nullptr, fp = fmemopen(nullptr, 16, "w"));
+ ASSERT_EQ(0, fclose(fp));
+}
+
+TEST(STDIO_TEST, fmemopen_fileno) {
+ // There's no fd backing an fmemopen FILE*.
+ FILE* fp = fmemopen(nullptr, 16, "r");
+ ASSERT_TRUE(fp != nullptr);
errno = 0;
- ASSERT_EQ(nullptr, fmemopen(nullptr, 0, "r"));
- ASSERT_EQ(EINVAL, errno);
+ ASSERT_EQ(-1, fileno(fp));
+ ASSERT_EQ(EBADF, errno);
+ ASSERT_EQ(0, fclose(fp));
+}
+
+TEST(STDIO_TEST, fmemopen_append_after_seek) {
+ // In BSD and glibc < 2.22, append mode didn't force writes to append if
+ // there had been an intervening seek.
+
+ FILE* fp;
+ char buf[] = "hello\0world";
+ ASSERT_NE(nullptr, fp = fmemopen(buf, sizeof(buf), "a"));
+ setbuf(fp, nullptr); // Turn off buffering so we can see what's happening as it happens.
+ ASSERT_EQ(0, fseek(fp, 0, SEEK_SET));
+ ASSERT_NE(EOF, fputc('!', fp));
+ EXPECT_EQ("hello!\0orld\0"s, std::string(buf, buf + sizeof(buf)));
+ ASSERT_EQ(0, fclose(fp));
+
+ memcpy(buf, "hello\0world", sizeof(buf));
+ ASSERT_NE(nullptr, fp = fmemopen(buf, sizeof(buf), "a+"));
+ setbuf(fp, nullptr); // Turn off buffering so we can see what's happening as it happens.
+ ASSERT_EQ(0, fseek(fp, 0, SEEK_SET));
+ ASSERT_NE(EOF, fputc('!', fp));
+ EXPECT_EQ("hello!\0orld\0"s, std::string(buf, buf + sizeof(buf)));
+ ASSERT_EQ(0, fclose(fp));
}
TEST(STDIO_TEST, open_memstream) {