diff options
Diffstat (limited to 'stream.c')
| -rw-r--r-- | stream.c | 58 |
1 files changed, 58 insertions, 0 deletions
@@ -65,6 +65,11 @@ #include "regex.h" #include "txr.h" +/* Adhere to ISO C rules about direction switching on update streams. */ +#ifndef __gnu_linux__ +#define CONFIG_STDIO_STRICT 1 +#endif + val stdin_s, stdout_s, stddebug_s, stderr_s, stdnull_s; val print_flo_precision_s, print_flo_digits_s, print_flo_format_s; @@ -348,6 +353,10 @@ val make_null_stream(void) return cobj(coerce(mem_t *, s), stream_s, &null_ops.cobj_ops); } +#if CONFIG_STDIO_STRICT +enum stdio_op { stdio_none, stdio_read, stdio_write }; +#endif + struct stdio_handle { struct strm_base a; FILE *f; @@ -365,6 +374,9 @@ struct stdio_handle { unsigned is_rotated; /* used by tail */ unsigned is_real_time; unsigned is_byte_oriented; +#if CONFIG_STDIO_STRICT + enum stdio_op last_op; +#endif #if HAVE_SOCKETS val family; val type; @@ -495,6 +507,30 @@ static int se_fflush(FILE *f) return ret; } +#if CONFIG_STDIO_STRICT +static void stdio_switch(struct stdio_handle *h, enum stdio_op op) +{ + if (h->last_op != op) { + if (h->f) { + switch (h->last_op) { + case stdio_read: + stdio_fseek(h->f, zero, strm_cur); + break; + case stdio_write: + se_fflush(h->f); + break; + default: + break; + } + } + + h->last_op = op; + } +} +#else +#define stdio_switch(X, Y) ((void) 0) +#endif + static int stdio_put_char_callback(int ch, mem_t *f) { int ret = se_putc(ch, coerce(FILE *, f)) != EOF; @@ -515,6 +551,8 @@ static val stdio_put_string(val stream, val str) if (h->f != 0) { const wchar_t *s = c_str(str); + stdio_switch(h, stdio_write); + while (*s) { if (!utf8_encode(*s++, stdio_put_char_callback, coerce(mem_t *, h->f))) return stdio_maybe_error(stream, lit("writing")); @@ -528,6 +566,7 @@ static val stdio_put_char(val stream, val ch) { struct stdio_handle *h = coerce(struct stdio_handle *, stream->co.handle); errno = 0; + stdio_switch(h, stdio_write); return h->f != 0 && utf8_encode(c_chr(ch), stdio_put_char_callback, coerce(mem_t *, h->f)) ? t : stdio_maybe_error(stream, lit("writing")); @@ -537,6 +576,7 @@ static val stdio_put_byte(val stream, int b) { struct stdio_handle *h = coerce(struct stdio_handle *, stream->co.handle); errno = 0; + stdio_switch(h, stdio_write); return h->f != 0 && se_putc(b, coerce(FILE *, h->f)) != EOF ? t : stdio_maybe_error(stream, lit("writing")); } @@ -545,6 +585,10 @@ static val stdio_flush(val stream) { struct stdio_handle *h = coerce(struct stdio_handle *, stream->co.handle); errno = 0; +#if CONFIG_STDIO_STRICT + if (h->f && h->last_op != stdio_write) + return t; +#endif return (h->f != 0 && se_fflush(h->f) == 0) ? t : stdio_maybe_error(stream, lit("flushing")); } @@ -697,6 +741,8 @@ static val stdio_get_char(val stream) if (h->f) { wint_t ch; + stdio_switch(h, stdio_read); + if (h->is_byte_oriented) { ch = se_getc(h->f); if (ch == 0) @@ -714,6 +760,9 @@ static val stdio_get_char(val stream) static val stdio_get_byte(val stream) { struct stdio_handle *h = coerce(struct stdio_handle *, stream->co.handle); + + stdio_switch(h, stdio_read); + if (h->f) { int ch = se_getc(h->f); return (ch != EOF) ? num(ch) : stdio_maybe_read_error(stream); @@ -956,6 +1005,9 @@ static void tail_strategy(val stream, unsigned long *state) */ if (!h->f) { h->f = newf; +#if CONFIG_STDIO_STRICT + h->last_op = stdio_none; +#endif (void) set_mode_props(m, stream); break; } @@ -992,6 +1044,9 @@ static void tail_strategy(val stream, unsigned long *state) fseek(newf, save_pos, SEEK_SET); fclose(h->f); h->f = newf; +#if CONFIG_STDIO_STRICT + h->last_op = stdio_none; +#endif (void) set_mode_props(m, stream); return; } @@ -1324,6 +1379,9 @@ static val make_stdio_stream_common(FILE *f, val descr, struct cobj_ops *ops) h->is_real_time = 0; #endif h->is_byte_oriented = 0; +#if CONFIG_STDIO_STRICT + h->last_op = stdio_none; +#endif #if HAVE_SOCKETS h->family = nil; h->type = nil; |