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90 lines
3.1 KiB
C
90 lines
3.1 KiB
C
#include "lib/mlrutil.h"
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#include "containers/slls.h"
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#include "containers/sllv.h"
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#include "mapping/mappers.h"
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typedef struct _mapper_label_state_t {
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slls_t* pnames;
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} mapper_label_state_t;
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static void mapper_label_usage(FILE* o, char* argv0, char* verb);
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static mapper_t* mapper_label_parse_cli(int* pargi, int argc, char** argv,
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cli_reader_opts_t* _, cli_writer_opts_t* __);
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static mapper_t* mapper_label_alloc(slls_t* pnames);
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static void mapper_label_free(mapper_t* pmapper, context_t* _);
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static sllv_t* mapper_label_process(lrec_t* pinrec, context_t* pctx, void* pvstate);
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// ----------------------------------------------------------------
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mapper_setup_t mapper_label_setup = {
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.verb = "label",
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.pusage_func = mapper_label_usage,
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.pparse_func = mapper_label_parse_cli,
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.ignores_input = FALSE,
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};
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// ----------------------------------------------------------------
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static void mapper_label_usage(FILE* o, char* argv0, char* verb) {
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fprintf(o, "Usage: %s %s {new1,new2,new3,...}\n", argv0, verb);
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fprintf(o, "Given n comma-separated names, renames the first n fields of each record to\n");
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fprintf(o, "have the respective name. (Fields past the nth are left with their original\n");
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fprintf(o, "names.) Particularly useful with --inidx or --implicit-csv-header, to give\n");
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fprintf(o, "useful names to otherwise integer-indexed fields.\n");
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fprintf(o, "Examples:\n");
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fprintf(o, " \"echo 'a b c d' | %s --inidx --odkvp cat\" gives \"1=a,2=b,3=c,4=d\"\n", argv0);
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fprintf(o, " \"echo 'a b c d' | %s --inidx --odkvp %s s,t\" gives \"s=a,t=b,3=c,4=d\"\n", argv0, verb);
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}
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static mapper_t* mapper_label_parse_cli(int* pargi, int argc, char** argv,
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cli_reader_opts_t* _, cli_writer_opts_t* __)
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{
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if ((argc - *pargi) < 2) {
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mapper_label_usage(stderr, argv[0], argv[*pargi]);
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return NULL;
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}
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slls_t* pnames = slls_from_line(argv[*pargi+1], ',', FALSE);
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*pargi += 2;
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return mapper_label_alloc(pnames);
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}
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// ----------------------------------------------------------------
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static mapper_t* mapper_label_alloc(slls_t* pnames) {
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mapper_t* pmapper = mlr_malloc_or_die(sizeof(mapper_t));
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mapper_label_state_t* pstate = mlr_malloc_or_die(sizeof(mapper_label_state_t));
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pstate->pnames = pnames;
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pmapper->pvstate = (void*)pstate;
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pmapper->pprocess_func = mapper_label_process;
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pmapper->pfree_func = mapper_label_free;
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return pmapper;
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}
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static void mapper_label_free(mapper_t* pmapper, context_t* _) {
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mapper_label_state_t* pstate = pmapper->pvstate;
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if (pstate->pnames != NULL)
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slls_free(pstate->pnames);
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free(pstate);
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free(pmapper);
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}
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// ----------------------------------------------------------------
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static sllv_t* mapper_label_process(lrec_t* pinrec, context_t* pctx, void* pvstate) {
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if (pinrec != NULL) {
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mapper_label_state_t* pstate = (mapper_label_state_t*)pvstate;
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lrece_t* pe = pinrec->phead;
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sllse_t* pn = pstate->pnames->phead;
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for ( ; pe != NULL && pn != NULL; pe = pe->pnext, pn = pn->pnext) {
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char* old_name = pe->key;
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char* new_name = pn->value;
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lrec_rename(pinrec, old_name, new_name, FALSE);
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}
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return sllv_single(pinrec);
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}
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else {
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return sllv_single(NULL);
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}
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}
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