diff options
Diffstat (limited to 'git-compat-util.h')
| -rw-r--r-- | git-compat-util.h | 203 |
1 files changed, 179 insertions, 24 deletions
diff --git a/git-compat-util.h b/git-compat-util.h index 685a0a4063..49d4029b8d 100644 --- a/git-compat-util.h +++ b/git-compat-util.h @@ -3,6 +3,23 @@ #define _FILE_OFFSET_BITS 64 + +/* Derived from Linux "Features Test Macro" header + * Convenience macros to test the versions of gcc (or + * a compatible compiler). + * Use them like this: + * #if GIT_GNUC_PREREQ (2,8) + * ... code requiring gcc 2.8 or later ... + * #endif +*/ +#if defined(__GNUC__) && defined(__GNUC_MINOR__) +# define GIT_GNUC_PREREQ(maj, min) \ + ((__GNUC__ << 16) + __GNUC_MINOR__ >= ((maj) << 16) + (min)) +#else + #define GIT_GNUC_PREREQ(maj, min) 0 +#endif + + #ifndef FLEX_ARRAY /* * See if our compiler is known to support flexible array members. @@ -25,7 +42,40 @@ #endif #endif -#define ARRAY_SIZE(x) (sizeof(x)/sizeof(x[0])) + +/* + * BUILD_ASSERT_OR_ZERO - assert a build-time dependency, as an expression. + * @cond: the compile-time condition which must be true. + * + * Your compile will fail if the condition isn't true, or can't be evaluated + * by the compiler. This can be used in an expression: its value is "0". + * + * Example: + * #define foo_to_char(foo) \ + * ((char *)(foo) \ + * + BUILD_ASSERT_OR_ZERO(offsetof(struct foo, string) == 0)) + */ +#define BUILD_ASSERT_OR_ZERO(cond) \ + (sizeof(char [1 - 2*!(cond)]) - 1) + +#if GIT_GNUC_PREREQ(3, 1) + /* &arr[0] degrades to a pointer: a different type from an array */ +# define BARF_UNLESS_AN_ARRAY(arr) \ + BUILD_ASSERT_OR_ZERO(!__builtin_types_compatible_p(__typeof__(arr), \ + __typeof__(&(arr)[0]))) +#else +# define BARF_UNLESS_AN_ARRAY(arr) 0 +#endif +/* + * ARRAY_SIZE - get the number of elements in a visible array + * <at> x: the array whose size you want. + * + * This does not work on pointers, or arrays declared as [], or + * function parameters. With correct compiler support, such usage + * will cause a build error (see the build_assert_or_zero macro). + */ +#define ARRAY_SIZE(x) (sizeof(x) / sizeof((x)[0]) + BARF_UNLESS_AN_ARRAY(x)) + #define bitsizeof(x) (CHAR_BIT * sizeof(x)) #define maximum_signed_value_of_type(a) \ @@ -46,6 +96,14 @@ #define unsigned_add_overflows(a, b) \ ((b) > maximum_unsigned_value_of_type(a) - (a)) +/* + * Returns true if the multiplication of "a" and "b" will + * overflow. The types of "a" and "b" must match and must be unsigned. + * Note that this macro evaluates "a" twice! + */ +#define unsigned_mult_overflows(a, b) \ + ((a) && (b) > maximum_unsigned_value_of_type(a) / (a)) + #ifdef __GNUC__ #define TYPEOF(x) (__typeof__(x)) #else @@ -137,6 +195,7 @@ #elif defined(_MSC_VER) #include "compat/msvc.h" #else +#include <sys/utsname.h> #include <sys/wait.h> #include <sys/resource.h> #include <sys/socket.h> @@ -178,7 +237,7 @@ typedef unsigned long uintptr_t; #else #define precompose_str(in,i_nfd2nfc) #define precompose_argv(c,v) -#define probe_utf8_pathname_composition(a,b) +#define probe_utf8_pathname_composition() #endif #ifdef MKDIR_WO_TRAILING_SLASH @@ -202,6 +261,8 @@ struct itimerval { #else #define basename gitbasename extern char *gitbasename(char *); +#define dirname gitdirname +extern char *gitdirname(char *); #endif #ifndef NO_ICONV @@ -218,9 +279,6 @@ extern char *gitbasename(char *); #endif #include <openssl/ssl.h> #include <openssl/err.h> -#ifdef NO_HMAC_CTX_CLEANUP -#define HMAC_CTX_cleanup HMAC_cleanup -#endif #endif /* On most systems <netdb.h> would have given us this, but @@ -245,6 +303,10 @@ extern char *gitbasename(char *); #define PRIuMAX "llu" #endif +#ifndef SCNuMAX +#define SCNuMAX PRIuMAX +#endif + #ifndef PRIu32 #define PRIu32 "u" #endif @@ -268,10 +330,6 @@ extern char *gitbasename(char *); #define _PATH_DEFPATH "/usr/local/bin:/usr/bin:/bin" #endif -#ifndef STRIP_EXTENSION -#define STRIP_EXTENSION "" -#endif - #ifndef has_dos_drive_prefix static inline int git_has_dos_drive_prefix(const char *path) { @@ -280,6 +338,14 @@ static inline int git_has_dos_drive_prefix(const char *path) #define has_dos_drive_prefix git_has_dos_drive_prefix #endif +#ifndef skip_dos_drive_prefix +static inline int git_skip_dos_drive_prefix(char **path) +{ + return 0; +} +#define skip_dos_drive_prefix git_skip_dos_drive_prefix +#endif + #ifndef is_dir_sep static inline int git_is_dir_sep(int c) { @@ -338,13 +404,14 @@ struct strbuf; /* General helper functions */ extern void vreportf(const char *prefix, const char *err, va_list params); -extern void vwritef(int fd, const char *prefix, const char *err, va_list params); extern NORETURN void usage(const char *err); extern NORETURN void usagef(const char *err, ...) __attribute__((format (printf, 1, 2))); extern NORETURN void die(const char *err, ...) __attribute__((format (printf, 1, 2))); extern NORETURN void die_errno(const char *err, ...) __attribute__((format (printf, 1, 2))); extern int error(const char *err, ...) __attribute__((format (printf, 1, 2))); +extern int error_errno(const char *err, ...) __attribute__((format (printf, 1, 2))); extern void warning(const char *err, ...) __attribute__((format (printf, 1, 2))); +extern void warning_errno(const char *err, ...) __attribute__((format (printf, 1, 2))); #ifndef NO_OPENSSL #ifdef APPLE_COMMON_CRYPTO @@ -374,6 +441,7 @@ static inline int const_error(void) extern void set_die_routine(NORETURN_PTR void (*routine)(const char *err, va_list params)); extern void set_error_routine(void (*routine)(const char *err, va_list params)); extern void set_die_is_recursing_routine(int (*routine)(void)); +extern void set_error_handle(FILE *); extern int starts_with(const char *str, const char *prefix); @@ -517,7 +585,7 @@ extern int git_lstat(const char *, struct stat *); #endif #define DEFAULT_PACKED_GIT_LIMIT \ - ((1024L * 1024L) * (sizeof(void*) >= 8 ? 8192 : 256)) + ((1024L * 1024L) * (size_t)(sizeof(void*) >= 8 ? 8192 : 256)) #ifdef NO_PREAD #define pread git_pread @@ -608,7 +676,6 @@ extern int git_vsnprintf(char *str, size_t maxsize, #ifdef __GLIBC_PREREQ #if __GLIBC_PREREQ(2, 1) #define HAVE_STRCHRNUL -#define HAVE_MEMPCPY #endif #endif @@ -622,14 +689,6 @@ static inline char *gitstrchrnul(const char *s, int c) } #endif -#ifndef HAVE_MEMPCPY -#define mempcpy gitmempcpy -static inline void *gitmempcpy(void *dest, const void *src, size_t n) -{ - return (char *)memcpy(dest, src, n) + n; -} -#endif - #ifdef NO_INET_PTON int inet_pton(int af, const char *src, void *dst); #endif @@ -648,6 +707,32 @@ extern void release_pack_memory(size_t); typedef void (*try_to_free_t)(size_t); extern try_to_free_t set_try_to_free_routine(try_to_free_t); +static inline size_t st_add(size_t a, size_t b) +{ + if (unsigned_add_overflows(a, b)) + die("size_t overflow: %"PRIuMAX" + %"PRIuMAX, + (uintmax_t)a, (uintmax_t)b); + return a + b; +} +#define st_add3(a,b,c) st_add(st_add((a),(b)),(c)) +#define st_add4(a,b,c,d) st_add(st_add3((a),(b),(c)),(d)) + +static inline size_t st_mult(size_t a, size_t b) +{ + if (unsigned_mult_overflows(a, b)) + die("size_t overflow: %"PRIuMAX" * %"PRIuMAX, + (uintmax_t)a, (uintmax_t)b); + return a * b; +} + +static inline size_t st_sub(size_t a, size_t b) +{ + if (a < b) + die("size_t underflow: %"PRIuMAX" - %"PRIuMAX, + (uintmax_t)a, (uintmax_t)b); + return a - b; +} + #ifdef HAVE_ALLOCA_H # include <alloca.h> # define xalloca(size) (alloca(size)) @@ -665,18 +750,85 @@ extern char *xstrndup(const char *str, size_t len); extern void *xrealloc(void *ptr, size_t size); extern void *xcalloc(size_t nmemb, size_t size); extern void *xmmap(void *start, size_t length, int prot, int flags, int fd, off_t offset); +extern void *xmmap_gently(void *start, size_t length, int prot, int flags, int fd, off_t offset); +extern int xopen(const char *path, int flags, ...); extern ssize_t xread(int fd, void *buf, size_t len); extern ssize_t xwrite(int fd, const void *buf, size_t len); extern ssize_t xpread(int fd, void *buf, size_t len, off_t offset); extern int xdup(int fd); +extern FILE *xfopen(const char *path, const char *mode); extern FILE *xfdopen(int fd, const char *mode); extern int xmkstemp(char *template); extern int xmkstemp_mode(char *template, int mode); extern int odb_mkstemp(char *template, size_t limit, const char *pattern); extern int odb_pack_keep(char *name, size_t namesz, const unsigned char *sha1); extern char *xgetcwd(void); +extern FILE *fopen_for_writing(const char *path); + +#define ALLOC_ARRAY(x, alloc) (x) = xmalloc(st_mult(sizeof(*(x)), (alloc))) +#define REALLOC_ARRAY(x, alloc) (x) = xrealloc((x), st_mult(sizeof(*(x)), (alloc))) -#define REALLOC_ARRAY(x, alloc) (x) = xrealloc((x), (alloc) * sizeof(*(x))) +/* + * These functions help you allocate structs with flex arrays, and copy + * the data directly into the array. For example, if you had: + * + * struct foo { + * int bar; + * char name[FLEX_ARRAY]; + * }; + * + * you can do: + * + * struct foo *f; + * FLEX_ALLOC_MEM(f, name, src, len); + * + * to allocate a "foo" with the contents of "src" in the "name" field. + * The resulting struct is automatically zero'd, and the flex-array field + * is NUL-terminated (whether the incoming src buffer was or not). + * + * The FLEXPTR_* variants operate on structs that don't use flex-arrays, + * but do want to store a pointer to some extra data in the same allocated + * block. For example, if you have: + * + * struct foo { + * char *name; + * int bar; + * }; + * + * you can do: + * + * struct foo *f; + * FLEX_ALLOC_STR(f, name, src); + * + * and "name" will point to a block of memory after the struct, which will be + * freed along with the struct (but the pointer can be repointed anywhere). + * + * The *_STR variants accept a string parameter rather than a ptr/len + * combination. + * + * Note that these macros will evaluate the first parameter multiple + * times, and it must be assignable as an lvalue. + */ +#define FLEX_ALLOC_MEM(x, flexname, buf, len) do { \ + (x) = NULL; /* silence -Wuninitialized for offset calculation */ \ + (x) = xalloc_flex(sizeof(*(x)), (char *)(&((x)->flexname)) - (char *)(x), (buf), (len)); \ +} while (0) +#define FLEXPTR_ALLOC_MEM(x, ptrname, buf, len) do { \ + (x) = xalloc_flex(sizeof(*(x)), sizeof(*(x)), (buf), (len)); \ + (x)->ptrname = (void *)((x)+1); \ +} while(0) +#define FLEX_ALLOC_STR(x, flexname, str) \ + FLEX_ALLOC_MEM((x), flexname, (str), strlen(str)) +#define FLEXPTR_ALLOC_STR(x, ptrname, str) \ + FLEXPTR_ALLOC_MEM((x), ptrname, (str), strlen(str)) + +static inline void *xalloc_flex(size_t base_len, size_t offset, + const void *src, size_t src_len) +{ + unsigned char *ret = xcalloc(1, st_add3(base_len, src_len, 1)); + memcpy(ret + offset, src, src_len); + return ret; +} static inline char *xstrdup_or_null(const char *str) { @@ -690,6 +842,9 @@ static inline size_t xsize_t(off_t len) return (size_t)len; } +__attribute__((format (printf, 3, 4))) +extern int xsnprintf(char *dst, size_t max, const char *fmt, ...); + /* in ctype.c, for kwset users */ extern const unsigned char tolower_trans_tbl[256]; @@ -760,6 +915,9 @@ static inline int strtoul_ui(char const *s, int base, unsigned int *result) char *p; errno = 0; + /* negative values would be accepted by strtoul */ + if (strchr(s, '-')) + return -1; ul = strtoul(s, &p, base); if (errno || *p || p == s || (unsigned int) ul != ul) return -1; @@ -865,9 +1023,6 @@ int access_or_die(const char *path, int mode, unsigned flag); /* Warn on an inaccessible file that ought to be accessible */ void warn_on_inaccessible(const char *path); -/* Get the passwd entry for the UID of the current process. */ -struct passwd *xgetpwuid_self(void); - #ifdef GMTIME_UNRELIABLE_ERRORS struct tm *git_gmtime(const time_t *); struct tm *git_gmtime_r(const time_t *, struct tm *); |