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60 lines
1.9 KiB
C
60 lines
1.9 KiB
C
#include <stdio.h> // For definition of EOF
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#include "input/byte_readers.h"
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#include "lib/mlr_globals.h"
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#include "lib/mlrutil.h"
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typedef struct _string_byte_reader_state_t {
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char* backing;
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char* p;
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char* pend;
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} string_byte_reader_state_t;
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static int string_byte_reader_open_func(struct _byte_reader_t* pbr, char* prepipe, char* backing);
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static int string_byte_reader_read_func(struct _byte_reader_t* pbr);
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static void string_byte_reader_close_func(struct _byte_reader_t* pbr, char* prepipe);
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// ----------------------------------------------------------------
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byte_reader_t* string_byte_reader_alloc() {
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byte_reader_t* pbr = mlr_malloc_or_die(sizeof(byte_reader_t));
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pbr->pvstate = NULL;
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pbr->popen_func = string_byte_reader_open_func;
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pbr->pread_func = string_byte_reader_read_func;
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pbr->pclose_func = string_byte_reader_close_func;
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return pbr;
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}
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void string_byte_reader_free(byte_reader_t* pbr) {
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free(pbr);
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}
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// ----------------------------------------------------------------
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static int string_byte_reader_open_func(struct _byte_reader_t* pbr, char* prepipe, char* backing) {
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// popen is a stdio construct, not an mmap construct, and it can't be supported here.
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if (prepipe != NULL) {
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fprintf(stderr, "%s: coding error detected in file %s at line %d.\n",
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MLR_GLOBALS.bargv0, __FILE__, __LINE__);
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exit(1);
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}
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string_byte_reader_state_t* pstate = mlr_malloc_or_die(sizeof(string_byte_reader_state_t));
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pstate->backing = backing;
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pstate->p = pstate->backing;
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pstate->pend = pstate->backing + strlen(pstate->backing);
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pbr->pvstate = pstate;
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return TRUE;
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}
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static int string_byte_reader_read_func(struct _byte_reader_t* pbr) {
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string_byte_reader_state_t* pstate = pbr->pvstate;
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if (pstate->p < pstate->pend) {
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return *(pstate->p++);
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} else {
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return EOF;
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}
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}
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static void string_byte_reader_close_func(struct _byte_reader_t* pbr, char* prepipe) {
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pbr->pvstate = NULL;
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}
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