miller/c/mapping/mapper_altkv.c
2020-01-26 23:08:40 -05:00

107 lines
3.2 KiB
C

#include <stdio.h>
#include "cli/argparse.h"
#include "lib/mlrutil.h"
#include "lib/mtrand.h"
#include "containers/sllv.h"
#include "mapping/mappers.h"
typedef struct _mapper_altkv_state_t {
ap_state_t* pargp;
} mapper_altkv_state_t;
static void mapper_altkv_usage(FILE* o, char* argv0, char* verb);
static mapper_t* mapper_altkv_parse_cli(int* pargi, int argc, char** argv,
cli_reader_opts_t* _, cli_writer_opts_t* __);
static mapper_t* mapper_altkv_alloc(ap_state_t* pargp);
static void mapper_altkv_free(mapper_t* pmapper, context_t* _);
static sllv_t* mapper_altkv_process(lrec_t* pinrec, context_t* pctx, void* pvstate);
// ----------------------------------------------------------------
mapper_setup_t mapper_altkv_setup = {
.verb = "altkv",
.pusage_func = mapper_altkv_usage,
.pparse_func = mapper_altkv_parse_cli,
.ignores_input = FALSE,
};
// ----------------------------------------------------------------
static void mapper_altkv_usage(FILE* o, char* argv0, char* verb) {
fprintf(o, "Usage: %s %s [no options]\n", argv0, verb);
fprintf(o, "Given fields with values of the form a,b,c,d,e,f emits a=b,c=d,e=f pairs.\n");
}
static mapper_t* mapper_altkv_parse_cli(int* pargi, int argc, char** argv,
cli_reader_opts_t* _, cli_writer_opts_t* __)
{
if ((argc - *pargi) < 1) {
mapper_altkv_usage(stderr, argv[0], argv[*pargi]);
return NULL;
}
char* verb = argv[*pargi];
*pargi += 1;
ap_state_t* pstate = ap_alloc();
if (!ap_parse(pstate, verb, pargi, argc, argv)) {
mapper_altkv_usage(stderr, argv[0], verb);
return NULL;
}
mapper_t* pmapper = mapper_altkv_alloc(pstate);
return pmapper;
}
// ----------------------------------------------------------------
static mapper_t* mapper_altkv_alloc(ap_state_t* pargp) {
mapper_t* pmapper = mlr_malloc_or_die(sizeof(mapper_t));
mapper_altkv_state_t* pstate = mlr_malloc_or_die(sizeof(mapper_altkv_state_t));
pstate->pargp = pargp;
pmapper->pvstate = pstate;
pmapper->pprocess_func = mapper_altkv_process;
pmapper->pfree_func = mapper_altkv_free;
return pmapper;
}
static void mapper_altkv_free(mapper_t* pmapper, context_t* _) {
mapper_altkv_state_t* pstate = pmapper->pvstate;
// Free the container
ap_free(pstate->pargp);
free(pstate);
free(pmapper);
}
// ----------------------------------------------------------------
static sllv_t* mapper_altkv_process(lrec_t* pinrec, context_t* pctx, void* pvstate) {
if (pinrec == NULL) { // End of input stream: emit null.
return sllv_single(NULL);
}
lrec_t* poutrec = lrec_unbacked_alloc();
int output_field_number = 1;
for (lrece_t* pe = pinrec->phead; pe != NULL; /* increment in loop */) {
if (pe->pnext == NULL) { // Odd-numbered field count
char* key = mlr_alloc_string_from_int(output_field_number);
char* value = mlr_strdup_or_die(pe->value);
lrec_put(poutrec, key, value, FREE_ENTRY_KEY | FREE_ENTRY_VALUE);
} else {
char* key = mlr_strdup_or_die(pe->value);
char* value = mlr_strdup_or_die(pe->pnext->value);
lrec_put(poutrec, key, value, FREE_ENTRY_KEY | FREE_ENTRY_VALUE);
}
output_field_number++;
pe = pe->pnext;
if (pe == NULL) {// Odd-numbered field count
break;
}
pe = pe->pnext;
}
lrec_free(pinrec);
return sllv_single(poutrec);
}