options.c

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#ifdef LINUX

#ifndef _GNU_SOURCE
#define _GNU_SOURCE
#endif

/* for realpath() */
#ifndef __USE_BSD
#define __USE_BSD
#endif

#endif /* LINUX */

#include <errno.h>
#include <limits.h>
#include <stdlib.h>
#include <stdio.h>
#include <sys/param.h>
#include <ctype.h>
#include <sys/stat.h>
#include <unistd.h>
#include <libgen.h>
#include <string.h>

#include "options.h"


void display_table(FILE*f,  char**table, int rows, int columns, int padding);


const char * options_banner_string = "";

void options_banner(const char*message) {
        options_banner_string = message;
}

char * strdup_(const char *s) {
        size_t len = strlen(s) + 1; /* null byte */
        char * t = (char*) malloc(len);
        memcpy(t,s,len);
        return t;
}


int get_int(int*p, const char*s) {
        int value;
        errno = 0;
        value = strtol(s, (char **)NULL, 10);
        if(0 == errno) {
                *p = value;
                return 1;
        } else return 0;
}

int get_double(double*p, const char*s) {
        char *endptr;
        *p = strtod(s, &endptr);
        return endptr != s;
}

int options_tolerant = 0;

int options_parse_args(struct option*ops, int argc, const char* argv[]) {
        int i;
        for (i=1; i<argc; i++) {
                const char * name = argv[i];
                while(*name == '-') name++;
                
                if(!strcmp("config_dump", name)) {
                        options_dump(ops, stdout, 0);
                        exit(0);
                }
                
                if(!strcmp("help",name) || !strcmp("h",name) ) {
                        options_print_help(ops, stdout);
                        exit(0);
                }
                
                if(!strcmp("config", name)) {
                        if(i>=argc-1) {
                                fprintf(stderr, "Please specify config file.\n");
                                if(!options_tolerant) return 0;
                        }
                        if(!options_parse_file(ops, ".", argv[i+1])) {
                                if(!options_tolerant) return 0;
                        }
                        i++;
                        continue;
                }
                
                struct option * o;
                if(0 == (o =options_find(ops, name)) ) {
                        fprintf(stderr, "Option '%s' not found (use -help to get list of options).\n", name);
                        if(!options_tolerant) return 0;
                }

                options_set_passed(o);
                if(options_requires_argument(o)) {
                        if(i>=argc-1) {
                                fprintf(stderr, "Argument %s needs value.\n", o->name);
                                if(!options_tolerant) return 0;
                        }
                        if(!options_set(o, argv[i+1])) {
                                if(!options_tolerant) return 0;
                        }
                        i++;
                } 

        } /* for */
        
        return 1;
}



void options_set_passed(struct option*o) {
        if(o->set_pointer) 
                *(o->set_pointer) = 1;
}

int options_requires_argument(struct option*o) {
        return o->value_pointer != 0;
}


int options_parse_stream(struct option*ops, const char*pwd, FILE*file) {
        #define MAX_LINE_LENGTH 10000
        char linesto[MAX_LINE_LENGTH];
        while(fgets(linesto, MAX_LINE_LENGTH-1, file)) {
                char *line=linesto; while(*line) { if(*line=='\n') *line=0; line++; }
                line = linesto;
                while(isspace(*line)) line++;
                if(*line == '#') continue;
                if(*line == '<') { line++;
                        while(isspace(*line)) line++;
                        if(!options_parse_file(ops, pwd, line)) {
                                if(!options_tolerant) return 0;
                        }
                        continue;
                }
                if(!*line) continue;
                /* Here starts the name; later we put a terminating 0 */
                const char * name = line;
                /* name continus until nonspace char */
                while(!isspace(*line)) line++;

                char empty[5] = "";
                char * value;
                if(*line == 0) value = empty; else {
                        *line = 0; /* terminating 0 for name */
                        line++;
                        /* ignore spaces */
                        while(isspace(*line)) line++;
                        /* ignore possible "=" */
                        if(*line == '=') line++;
                        /* ignore spaces */
                        while(isspace(*line)) line++;

                        /* here starts the value */
                        value = line;
                        /* delete final spaces */
                        int len = strlen(value);
                        while(isspace(value[len-1]) && len > 0) {
                                value[len-1] = 0; len--;
                        }
                }
                                
                if(!options_try_pair(ops, name, value) && !options_tolerant) {
                        return 0;
                }
        }
        return 1;
}

int options_parse_file(struct option*ops, const char*pwd, const char*filename) {
        char concat[PATH_MAX*2+1];

        if(filename[0] != '/') {
                strcpy(concat, pwd);
                strcat(concat, "/");
                strcat(concat, filename);
        } else {
                strcpy(concat, filename);       
        }
        
        char resolved_path[PATH_MAX];
        char *resolved;
        if(! (resolved = realpath(concat, resolved_path))) {
                fprintf(stderr, "Could not resolve '%s' ('%s').\n", concat, resolved); 
                return 0;
        }

        const char * newdir = dirname(resolved);
        if(!newdir) {
                fprintf(stderr, "Could not get dirname for '%s'.\n",  resolved); 
                free(resolved);
                return 0;
        }
        
        FILE * file;
        file = fopen(resolved,"r");
        if(file==NULL) {
                fprintf(stderr, "Could not open '%s': %s.\n", resolved, strerror(errno)); 
                /* free(resolved); */
                return 0;
        }
        
        /* free(resolved); */
        return options_parse_stream(ops, newdir, file);
}


struct option * options_find(struct option*ops, const char * name) {
        int j;
        for(j=0;options_valid(ops+j);j++) 
                if(!strcmp(name,ops[j].name)) 
                return ops+j;
        
        return 0;
}

int options_try_pair(struct option*ops, const char*name, const char*value) {
        struct option* o;
        if(0 == (o = options_find(ops, name))) {
                /* error, option does not exist */
                fprintf(stderr, "Option '%s' does not exist.\n", name);
                return 0;
        }
        return options_set(o, value);
}

int options_valid(struct option*o) {
        return o->name != 0;
}

int options_set(struct option*o, const char*value) {
        switch(o->type) {       
                case(OPTION_INT): {
                        int * value_pointer = (int*) o->value_pointer;
                        int ok = get_int(value_pointer, value);
                        if(!ok) {
                                fprintf(stderr, "Could not parse int: '%s' = '%s'.\n", o->name, value);
                                return 0;
                        }
                        return 1;
                }

                case(OPTION_STRING): {
                        char** value_pointer = (char**) o->value_pointer;
                        *value_pointer = (char*) strdup_(value);
/*                      fprintf(stderr, 
                                "String %s, value_pointer=%p void pointer=%p *value_pointer=%p result=%s\n"
                         ,argv[i+1], value_pointer, o->op[j].value_pointer, *value_pointer,
                         *value_pointer);*/
                        return 1;
                }

                case(OPTION_DOUBLE): {
                        double * value_pointer = (double*) o->value_pointer;
                        int ok = get_double(value_pointer, value);
                        if(!ok) {
                                fprintf(stderr, "Could not parse double: '%s' = '%s'.\n", o->name, value);
                                return 0;
                        }
                        return 1;
                }

                case(OPTION_ALTERNATIVE): {
                        int * value_pointer = (int*) o->value_pointer;
                        struct option_alternative * a = o->alternative;
                        for(; a->label; a++) {
                                if( !strcasecmp(a->label, value) ) {
                                        *value_pointer = a->value;
                                        return 1;
                                }
                        }
                        fprintf(stderr, "Could not recognize '%s' as one of the alternative for %s: ", 
                                value, o->name);
                        
                        for(a = o->alternative; a->label; a++) {
                                fprintf(stderr, "\"%s\"", a->label);
                                if( (a+1)->label )      fprintf(stderr, ", ");
                        }
                        fprintf(stderr, ".\n");
                        return 0;
                }
                
                
                
                default: {
                        /* XXX ERROR */
                        fprintf(stderr, "Could not parse type %d: '%s' = '%s'.\n", (int) o->type, o->name, value);
                        return 0;
                }
        }
}

const char*options_value_as_string(struct option*o);

void display_table(FILE*f,  char**table, int rows, int columns, int padding) {
        int col_size[columns];
        
        int i,j;
        for(j=0;j<columns;j++)  {
                col_size[j]=0;
                for(i=0;i<rows;i++) {
                        const char * s = table[j+i*columns];
                        col_size[j] = MAX(col_size[j], (int) strlen(s));
                }
                col_size[j] += padding;
        }
        
        for(i=0;i<rows;i++) {
                for(j=0;j<columns;j++)  {
                        const char * s = table[j+i*columns];
                        /* don't add padding to last column */
                        if(j != columns - 1)
                                fprintf(f, "%s%*s", s, (int)(col_size[j]-strlen(s)), "");
                        else
                                fputs(s, f);
                }
                fprintf(f, "\n");
        }
}

void options_dump(struct option * options, FILE*f, int write_desc) {
        int n; for (n=0;options_valid(options+n);n++);

        int nrows = n + 2;
        char**table = malloc(sizeof(char*)*nrows*3);

        int row = 0;
        if(write_desc) {
                table[row*3 +0] = strdup_("Option name");
                table[row*3 +1] = strdup_("Default");
                table[row*3 +2] = strdup_("Description");
                row++;
                table[row*3 +0] = strdup_("-----------");
                table[row*3 +1] = strdup_("-------");
                table[row*3 +2] = strdup_("-----------");
                row++;
        } else {
                table[row*3 +0] = strdup_("");
                table[row*3 +1] = strdup_("");
                table[row*3 +2] = strdup_("");
                row++;
                table[row*3 +0] = strdup_("");
                table[row*3 +1] = strdup_("");
                table[row*3 +2] = strdup_("");
                row++;
        }
        
        int i;
        for (i=0;i<n;i++) {
                table[row*3 +0] = strdup_(options[i].name);
                table[row*3 +1] = strdup_(options_value_as_string(options+i));
                table[row*3 +2] = write_desc ? strdup_(options[i].desc) : strdup_(""); 

                if( write_desc)
                if(options[i].type == OPTION_ALTERNATIVE) {
                        char extended[1000];
                        strcat(extended, options[i].desc);
                        strcat(extended, "  Possible options are: ");
        
                        struct option_alternative * a = options[i].alternative;
                        for(; a->label; a++) {
                                strcat(extended, "\"");
                                strcat(extended, a->label);
                                strcat(extended, "\"");
                                if(a->desc) {
                                strcat(extended, ": ");
                                strcat(extended, a->desc);
                                } else {
                                }
                                if((a+1)->label)
                                        strcat(extended, ", ");
                        }       
                        strcat(extended, ".");
                        
                        table[row*3 +2] =  strdup_(extended);   
                }
                
                row ++;
        }

        display_table(f, table, nrows, 3, 2);

        int a; for(a=0;a<nrows*3;a++) free((void*)table[a]);
        free((void*)table);
}

void options_print_help(struct option * options, FILE*f) {
        fprintf(f, "%s", options_banner_string);
        fprintf(f, 
        "Generic options: \n"
        "  -help          Displays this help.\n"
        "  -config_dump   Dumps the configuration on the standard output. \n"
        "  -config FILE   Loads a config file in the format used by config_dump.\n"
        "\n");
        
        options_dump(options, f, 1);
}

static char options_value_as_string_buf[1000];
const char*options_value_as_string(struct option*o) {
        if(!o->value_pointer) {
                return "NULL";
        }
        
        switch(o->type) {
                case(OPTION_INT): {
                        int * value_pointer = (int*) o->value_pointer;
                        sprintf(options_value_as_string_buf, "%d", *value_pointer);
                        break;
                }

                case(OPTION_STRING): {
                        char** value_pointer = (char**) o->value_pointer;
                        sprintf(options_value_as_string_buf, "%s", *value_pointer); /* should I add "" ? */
                        break;
                }
                
                case(OPTION_DOUBLE): {
                        double * value_pointer = (double*) o->value_pointer;
                        sprintf(options_value_as_string_buf, "%g", *value_pointer);
                        break;
                }
                
                case(OPTION_ALTERNATIVE): {
                        int * value_pointer = (int*) o->value_pointer;
                        struct option_alternative * a = o->alternative;
                        for(; a->label; a++) {
                                if( a->value == *value_pointer )
                                        sprintf(options_value_as_string_buf, "%s", a->label);
                        }
                        break;
                }
                
                default: 
                strcpy(options_value_as_string_buf, "?");
        } /* switch */  
        
        return options_value_as_string_buf;
}