intercept fget* family (779da1d2) · Commits · David Auer / gekkofs

ifs/include/preload/passthrough.hpp

+5 −0

Original line number	Diff line number	Diff line
		@@ -35,6 +35,11 @@ extern void* libc_setvbuf;

		extern void* libc_putc;
		extern void* libc_fputc;
		extern void* libc_fputs;
		extern void* libc_getc;
		extern void* libc_fgetc;
		extern void* libc_fgets;
		extern void* libc_ungetc;

		extern void* libc_mkdir;
		extern void* libc_mkdirat;

ifs/src/preload/intcp_functions.cpp

+80 −2

Original line number	Diff line number	Diff line
		@@ -377,7 +377,7 @@ int putc(int c, FILE *stream) {
		return EOF;
		}
		}
		return (reinterpret_cast<decltype(&putc)>(libc_putc))(c, stream);
		return LIBC_FUNC(putc, c, stream);
		}

		int fputc(int c, FILE *stream) {
		@@ -390,7 +390,85 @@ int fputc(int c, FILE *stream) {
		return EOF;
		}
		}
		return (reinterpret_cast<decltype(&fputc)>(libc_fputc))(c, stream);
		return LIBC_FUNC(fputc, c, stream);
		}

		int fputs(const char s, FILE stream) {
		init_passthrough_if_needed();
		if(CTX->initialized() && (stream != nullptr)) {
		auto fd = file_to_fd(stream);
		if(CTX->file_map()->exist(fd)) {
		CTX->log()->error("{}() NOT SUPPORTED", __func__);
		errno = ENOTSUP;
		return EOF;
		}
		}
		return LIBC_FUNC(fputs, s, stream);
		}

		int getc(FILE *stream) {
		init_passthrough_if_needed();
		if(CTX->initialized() && (stream != nullptr)) {
		auto fd = file_to_fd(stream);
		if(CTX->file_map()->exist(fd)) {
		CTX->log()->error("{}() NOT SUPPORTED", __func__);
		errno = ENOTSUP;
		return EOF;
		}
		}
		return LIBC_FUNC(getc, stream);
		}

		int fgetc(FILE *stream) {
		init_passthrough_if_needed();
		if(CTX->initialized() && (stream != nullptr)) {
		auto fd = file_to_fd(stream);
		if(CTX->file_map()->exist(fd)) {
		CTX->log()->error("{}() NOT SUPPORTED", __func__);
		errno = ENOTSUP;
		return EOF;
		}
		}
		return LIBC_FUNC(fgetc, stream);
		}

		char* fgets(char* s, int size, FILE* stream) {
		init_passthrough_if_needed();
		if(CTX->initialized() && (stream != nullptr)) {
		auto fd = file_to_fd(stream);
		if(CTX->file_map()->exist(fd)) {
		CTX->log()->trace("{}() [fd: {}, size: {}]", __func__, fd, size);
		auto ret = adafs_read(fd, s, size - 1);
		CTX->log()->debug("{}() read {} bytes", __func__, ret);
		if(ret > 0) {
		char* nl_ptr = static_cast<char*>(memchr(s, '\n', size - 1));
		assert((nl_ptr - s) < size);
		if(nl_ptr != nullptr) {
		CTX->log()->debug("{}() found new line char at {}", __func__, (nl_ptr - s));
		nl_ptr[1] = '\0';
		} else {
		s[size - 1] = '\0';
		}
		return s;
		} else {
		return nullptr;
		}
		}
		}
		return LIBC_FUNC(fgets, s, size, stream);
		}

		int ungetc(int c, FILE *stream) {
		init_passthrough_if_needed();
		if(CTX->initialized() && (stream != nullptr)) {
		auto fd = file_to_fd(stream);
		if(CTX->file_map()->exist(fd)) {
		CTX->log()->error("{}() NOT SUPPORTED", __func__);
		errno = ENOTSUP;
		return EOF;
		}
		}
		return LIBC_FUNC(ungetc, c, stream);
		}

		/**** FILE OPS ****/

ifs/src/preload/passthrough.cpp

+10 −0

Original line number	Diff line number	Diff line
		@@ -35,6 +35,11 @@ void* libc_setvbuf;

		void* libc_putc;
		void* libc_fputc;
		void* libc_fputs;
		void* libc_getc;
		void* libc_fgetc;
		void* libc_fgets;
		void* libc_ungetc;

		void* libc_mkdir;
		void* libc_mkdirat;
		@@ -141,6 +146,11 @@ void init_passthrough_() {

		libc_putc = dlsym(libc, "putc");
		libc_fputc = dlsym(libc, "fputc");
		libc_fputs = dlsym(libc, "fputs");
		libc_getc = dlsym(libc, "getc");
		libc_fgetc = dlsym(libc, "fgetc");
		libc_fgets = dlsym(libc, "fgets");
		libc_ungetc = dlsym(libc, "ungetc");

		libc_mkdir = dlsym(libc, "mkdir");
		libc_mkdirat = dlsym(libc, "mkdirat");